Disastrous Consequences (solved: fog with Intrepid lensboard)

[brianentz]

So, I'm new to LF and I just got my Intrepid 4x5 and an assortment of lenses including my main lens - Nikon 90mm. Went backpacking. Processed the film and found that everything shot with that lens came out horribly wrong. I guess it needs to be serviced or replaced. Ever seen anything like this? I made a couple exposures with my Rodenstock 150 and that came out beautifully. Any idea what could be wrong?
208366208367208368

[Jim Noel]

EIther your Nikon 90 mm is not a wide angle lens,or you are missing an element. I suspect it is not a WA. Does the ID on the lens indicat WA?

[PRJ]

What is your lensboard made out of?

[Bruce Watson]

Any idea what could be wrong?

No, not really. Sorry.

OTOH, you got your first lesson in LF -- the ground glass does not lie. It took me a lot longer than my first trip to fully, viscerally, understand that. Once I latched hold of that concept I wasted a whole lot less film, and my "winners" became a much higher percentage of my shots.

You done good. Stuff like this is how we learn.

[Dan Fromm]

Which filter did you put on it? I ask because there's not too bad image in the corners.

A picture of the lens on its board would be helpful. Side views, so we can read the ID etc. on the front of the barrel.

[BrianShaw]

Did it look like that on the ground glass?

[Kiwi7475]

They look just like pictures taken with my Holga!

/s

If it’s not the lens it does look like some light leak... almost like the lens board is not totally light proof...?

[Jody_S]

Put the lens on the camera, shutter closed, point it at a bright light, remove the camera back and see where the light leak is. It appears to be all around the lens, with the rear element blocking the circle in the middle from getting fully exposed to the light leak. Perhaps you re-purposed a lens board that had holes drilled for mounting a flange with screws?

[brianentz]

Here are a couple pics. Could this not actually be a wide angle lens? Could it have simply been that the lens was loose on the lens board? I sure appreciate your response. 208376208377208380

[brianentz]

On the various pictures that came out with the same defects I used a couple different filters. Orange and a polarizer separately.

[brianentz]

I should add that in the field I discovered the rear element and lensboard were loose, but I thought I took care of it (without tools)

[Two23]

It's a good wide angle lens. Note the gap between the rear of the shutter and the lens board. I'm suspecting there is a light leak around the shutter as Jody suggested.


Kent in SD

[brianentz]

No, but the perimeter of the image on the ground glass was dimmer as I don't have a fresnel lens - yet.

[brianentz]

Here's a close up of the lens elements and the lens board contacts. 208378208379208378208381

[Jim Noel]

It appears the rear element may not be screwed completely into the shutter.

[Nodda Duma]

Someone posted the exact same problem either here or on photrio a few months ago. The cause were the Intrepid lens boards: Thry may look opaque but they are not! They do not block the full spectrum.

You can see an image in the center and the periphery is overexposed.

Put your lens on a different lensboard and it will be fine.

[Kiwi7475]

Someone posted the exact same problem either here or on photrio a few months ago. The cause were the Intrepid lens boards: Thry may look opaque but they are not! They do not block the full spectrum.

You can see an image in the center and the periphery is overexposed.

Put your lens on a different lensboard and it will be fine.

They’re not aluminum????

[Two23]

Someone posted the exact same problem either here or on photrio a few months ago. The cause were the Intrepid lens boards: Thry may look opaque but they are not! They do not block the full spectrum.

You can see an image in the center and the periphery is overexposed.

Put your lens on a different lensboard and it will be fine.

WOW! Never would have guessed that but looking at the images that looks correct. The rear bell of the lens was shading the negative.


Kent in SD

[brianentz]

This picture shows a gap between the locking nut and the lens board. I dismantled and found that it didn't quite fit into the hole. So I enlarged the hole and now the nut goes right up against the lens board. Could that have caused such a problem? I can't figure how. I guess now I need to make some test exposures with this adjustment.

[reddesert]

Here's a close up of the lens elements and the lens board contacts. 208378208379208378208381

Picture 4 here shows the retaining ring not fully seated into the lens board. When this happens, the rear element may also not be fully screwed into the back of the shutter, and there could be light leaks around the lensboard hole.

As a quick and dirty check on whether the lensboard is not fully opaque and that could also be causing problems, you could try lining the back of the lensboard with something opaque, even aluminum foil (not ideal because it's shiny, but ok for a test).

[Duolab123]

I have the same lens, the board needs to be cut to fit the shutter. There's a fellow in Chicago that makes marvelous lens boards for cheap. He's on Ebay. The shutter needs to be fully engaged and the shutter mounting nut should also fit into the lens board hole. Buy a flat metal shutter wrench to tighten the nut down.after all that's in place screw in the rear element.
If you found the shutter loose I would suspect that's where your light strike came from.

[Jody_S]

Assuming you only pull the dark slide just before taking a shot, and put it back in immediately after, that's a big light leak that should be quite easy to find by doing a light test. Nodda Duma says some of their lens boards aren't fully opaque, that would explain a really diffuse light leak like this one.

[Kiwi7475]

See here:


https://www.largeformatphotography.info/forum/showthread.php?158981-Lens-board-light-leak-lens-board-question/page2

[Dugan]

Fun detective work!
Now that you know how to seat the lens and retaining ring (it's not a "nut") properly...take the lens & shutter assembly off of the lens board, and paint the back side of the lens board with flat black paint....a couple coats.
Let it dry, and reinstall the lens & shutter assembly.
....and Voila!

[brianentz]

Unbelievably, the lens board appears to be the problem. It is a genuine Intrepid lensboard and it isn't lightproof. I put a flashlight up against the lensboard and it just shines through. 208383
It sure looked light proof. I'm aghast. I will let Intrepid know about this.

[brianentz]

Not "appears" to be the problem - IS the problem. I read the comments but couldn't believe that it could actually be anything other than light proof.

[Kiwi7475]

If you read the thread I posted you’ll see they’re aware and solved it by going from FR4 to Aluminum.

I’ve done my fair share of PCBs in my early days and know quite well FR4 is not light proof....

But yes, contact them and I’m sure they’ll send you a replacement in aluminum.

[brianentz]

Yes, I read those notes, but after earlier comment. I'm sure they'll send me a new one. Still - amazing that could happen. Well, problem solved, I guess.

[md-photo]

Translucent board?? How does something like that go into production without testing?

[John Layton]

speechless...

[Max Grew]

Unbelievably, the lens board appears to be the problem. It is a genuine Intrepid lensboard and it isn't lightproof. I put a flashlight up against the lensboard and it just shines through. 208383
It sure looked light proof. I'm aghast. I will let Intrepid know about this.

Hello, I believe Naomi has all ready spoken to you about this but I just wanted to personally apologise that you received a faulty lens board, they are supposed to have a rubberised light proof backing (similar material to our bellows) and the ones you received did not have the backing applied. I'm really sorry this wasn't spotted before they were sent out. We have been through all our current stock of lens boards and can confirm they are all light proof. We will have some replacement boards on the way to you tomorrow and more than happy to add in a box of film to make up for the lost sheets.

If you have any questions feel free to reply to me on here or Naomi's email

- Max

[Duolab123]

Wow, that's a fast response from a supplier. Well done.

[Bernice Loui]

Not impressed. Very possible reason for using FR4 which is a printed circuit board material very common in the electronics industry is cost. FR4 is low cost and easy to have made in the shape needed due to the widely availability of manufacturing facilities and low cost for the finished part. There is no possible way FR4 is light tight as delivered or painted. If rubberized, that coating has a very good possibility of developing pin holes light leaks as the material ages and flakes off in unpredictable ways. This is every reason to never used any lens boards made with this material and coated with any material.

Given the cost of photographic materials, resourced required to make images and the fact images made could be near impossible to replicate, the risk of a pin hole or worst light leak due to a known problem lens board design is not tolerable in any way.

IMO, ditch the problem maker, apply what is needed to get a proper lens board made of aluminum or wood as these are well proven lens board materials with a record and history of being durable-reliable.

Any manufacture that is willing to sell a product like lens boards made of FR4 then coated says much about the company and those involved with their product design and manufacturing.



Bernice

[Max Grew]

Not impressed. Very possible reason for using FR4 which is a printed circuit board material very common in the electronics industry is cost. FR4 is low cost and easy to have made in the shape needed due to the widely availability of manufacturing facilities and low cost for the finished part. There is no possible way FR4 is light tight as delivered or painted. If rubberized, that coating has a very good possibility of developing pin holes light leaks as the material ages and flakes off in unpredictable ways. This is every reason to never used any lens boards made with this material and coated with any material.

Given the cost of photographic materials, resourced required to make images and the fact images made could be near impossible to replicate, the risk of a pin hole or worst light leak due to a known problem lens board design is not tolerable in any way.

IMO, ditch the problem maker, apply what is needed to get a proper lens board made of aluminum or wood as these are well proven lens board materials with a record and history of being durable-reliable.

Any manufacture that is willing to sell a product like lens boards made of FR4 then coated says much about the company and those involved with their product design and manufacturing.



Bernice

Hi Bernice,

thanks for your thoughts, rubberised was probably the wrong term to use, the coating is Vinyl, tested thoroughly and holds up well under heavy use. no need to worry about pinholes in the material. The reason we have gone with fibreglass for the boards is as you state, we can utilise the massive PCB manufacturing industry and have thousands of them made for considerably less than an aluminium or wood equivalent, a saving we pass onto the customer. Despite your assumptions about the boards they do work very well and are just as good as an aluminium or wood board, and a bit lighter too!

[Bernice Loui]

Make a correct lens board out of wood or aluminum. Cost reduction on an absolutely crucial part (lens board) is absurd.

One sheet of 4x5 color transparency film about $5-7 USD, add processing per sheet. Lose one sheet of film due to a light leak of any kind results in the lost of those materials and cost involved. More important, lost of an image that is often impossible to replicate.


~"Penny Wise _ Pound Foolish"~


No possible way you're going to convince me a coated FR4 lens board will be as good and reliable as an aluminum or high quality wood lens board. Having been around FR4 via the electronics industry for decades, this is simply not a good idea or choice.

If the aluminum or wood lens board cost $20 - $50 or more, so be it as losing any sheet of film due to an unexpected light leak is simply unacceptable
in every condition.


Bernice




Hi Bernice,

thanks for your thoughts, rubberised was probably the wrong term to use, the coating is Vinyl, tested thoroughly and holds up well under heavy use. no need to worry about pinholes in the material. The reason we have gone with fibreglass for the boards is as you state, we can utilise the massive PCB manufacturing industry and have thousands of them made for considerably less than an aluminium or wood equivalent, a saving we pass onto the customer. Despite your assumptions about the boards they do work very well and are just as good as an aluminium or wood board, and a bit lighter too!

[Havoc]

With waterjet cutting available very easy and low cost I see no advantage in using FR4. In fact unclad FR4 might be even more expensive than plain alu as it is a less standard product than copper clad FP4. Neither is the precision used in PCB manufacturing needed. And making a .dxf of something as simple as a lens board isn't that hard. Shouldn't cost more than a few money units ($/£/€) piece.

I agree with Bernice that this is a badly inspired choice.

[Kiwi7475]

Go to eBay and buy a CNC aluminum lens board from Luland for like $13.99 free shipping.
No issues, and will last forever.

[Bernice Loui]

Cost to water jet cut FR4 or aluminum is about the same. Since the FR4 is coated, finishing cost would be very similar. Very possible raw material cost would be more for the FR4 as non-copper plated FR4 is not a standard item.


Bernice



With waterjet cutting available very easy and low cost I see no advantage in using FR4. In fact unclad FR4 might be even more expensive than plain alu as it is a less standard product than copper clad FP4. Neither is the precision used in PCB manufacturing needed. And making a .dxf of something as simple as a lens board isn't that hard. Shouldn't cost more than a few money units ($/£/€) piece.

I agree with Bernice that this is a badly inspired choice.

[Tin Can]

I second that, I have bought many lensboards from Luland


Go to eBay and buy a CNC aluminum lens board from Luland for like $13.99 free shipping.
No issues, and will last forever.

[Max Grew]

With waterjet cutting available very easy and low cost I see no advantage in using FR4. In fact unclad FR4 might be even more expensive than plain alu as it is a less standard product than copper clad FP4. Neither is the precision used in PCB manufacturing needed. And making a .dxf of something as simple as a lens board isn't that hard. Shouldn't cost more than a few money units ($/£/€) piece.

I agree with Bernice that this is a badly inspired choice.

I really do appreciate everyones opinions on this but FR4 is a great choice for our lens boards I will explain why,

Aluminium boards = Cutting (water jet or laser) + Deburring + Tumbling or Linishing + Anodising + Laser engraving our logo + high shipping cost when done at our scale = surprisingly high cost of lens board

Wood boards = it's very hard to find 2mm thick wood that can be easily held down and cut. making the 100s of boards we need each month would be impracticle

FR4 = board arrives all ready duburred, finished in black and with logo on it as this is all part of standard pre existing product manufacturing process (PCBs) they are excellent quality light weight and work just as well as any other material we have used.

We used to make boards out of aluminium using the method above, it was a pain. I wouldn't even bother trying to make them out of wood. Work holding 2mm wood is nightmare inducing. I know lots of people on here have all sorts of experience in a range of fields but as someone who has had to make literally tens of thousands of lens boards over the last 6 years the FR4 process is miles better than anything else we have tried, and we have tried all sorts! maybe its not your cup of tea but they make for great lens boards and the whole production process is so simple we would never look back.

if you are still not sure then we will have to just agree to disagree :p

- Max

[grat]

Cost to water jet cut FR4 or aluminum is about the same. Since the FR4 is coated, finishing cost would be very similar. Very possible raw material cost would be more for the FR4 as non-copper plated FR4 is not a standard item.


Says who? Grainger and McMaster-Carr both sell GR10-FR4, uncoated, for about $10.70/sq ft. for roughly the same thickness as a lensboard.

Their aluminum prices are twice that for the same thickness in aluminum sheet, and around $15 /sq. ft. for aluminum plate.

That's all retail-- I assume bulk/wholesale purchase would be cheaper, but I would also expect the relative pricing to be about the same.

If I were Max, I think I'd feel somewhat insulted that someone felt I hadn't done my homework properly before making such a choice.

[Kiwi7475]

Says who? Grainger and McMaster-Carr both sell GR10-FR4, uncoated, for about $10.70/sq ft. for roughly the same thickness as a lensboard.

Their aluminum prices are twice that for the same thickness in aluminum sheet, and around $15 /sq. ft. for aluminum plate.

That's all retail-- I assume bulk/wholesale purchase would be cheaper, but I would also expect the relative pricing to be about the same.

If I were Max, I think I'd feel somewhat insulted that someone felt I hadn't done my homework properly before making such a choice.

Since you can at least get 4 boards from one square foot sheet, the cost difference is either $2.67 in FR4 or $5.35 in aluminum sheet or $3.75 for plate. None of that has a strong bearing on the cost. The real cost difference must come from the manufacturing of the part depending on the material, not from the material cost alone. I think that’s what Max was trying to say.

What I wonder is what tests have they done to ensure longevity. I can’t see these coated FR4 boards lasting year after year. But their business model is not necessarily that of say Linhof, which become heirlooom.

To each it’s own. For the cost, I go with Luland. Options exists if your willing to look or listen.

[djdister]

Designing the front standard to use a "common" existing lens board size (e.g. Technika) would be my suggestion. They are common, easily available, and interchangeable with other 4x5 cameras.

[Peter De Smidt]

The camera is compatible with Sinar lens boards, which are very common. Critics have had their say. Why not leave it at that? If not, the end result will likely be another manufacturer who won't post here.

[brianentz]

Indeed, Intrepid is mailing me a replacement lens board and a box of film for my troubles. (BIG troubles). Right now, I'm just glad that I figured this out. Still, I love my new Intrepid Mark 4 camera and my whole 4x5" set up. Got to get out there and get some other shots. Here's the only shot from the backpacking trip that came out because I used a different lens. 208397

[Gary Beasley]

Makes me wonder why the copper clad FR4 was not used as the metal would make the board quite light tight especially if the extra coating is used.

[Bernice Loui]

If Sinar lens boards fits this Intrepid camera, simply use them and move on.

Batting about saving a few $ here or there is absurd given the overall cost and resources required to produce images using a view camera.

For comparison, Sinar lens boards have a light trap groove all around the camera side of the lens board. Last versions of these Sinar lens boards are cast aluminum with the Sinar logo on the lens side of the board. The light trap groove is part of the casting with precision machined registration areas on each of the four corners.

The Sinar camera standard has a matching raised area that fits into the lens board groove to act as a very effective light trap with precision lens board registration to the camera standard.

IMO, anything less is not going to be reliable or have the degree of precision needed for some view camera images that demand this degree of precision and stability from a view camera.


Bernice

[Tobias Key]

If you are in the UK and want a new lens board ffordes.com has pattern Linhof fit boards made in aluminium for £19. I bought three and they fit and work perfectly. I don't think the potential downsides of the Intrepid boards is worth saving £4 for. That's literally one sheet of 4x5.

[Havoc]

Says who? ....

If I were Max, I think I'd feel somewhat insulted that someone felt I hadn't done my homework properly before making such a choice.

As someone who has designed and have produced both pcb's and metal parts as a commercial process I have done similar homework repeatedly.

I won't comment on wood as yes, that might be troublesome. But why anodising the alu and then laser engraving it? Every lensboard in alu I have seen is just painted and screen printed (if that). The Sinar one I have here is painter alu with a sticker logo! Something that can be done in the same shop compared to anodising and laser engraving which would mean transporting between shops, with each time packing and for the laser engraving, positioning as well. I can imagine that this is expensive! Just getting it through a painting tunnel and then a screen print would be far cheaper and better (fit for this purpose).

I really don't get the idea of comparing FR4 with vinyl coating which I find "cheap" to anodised and laser engraved which I find "premium".

Being honest I really like the Intrepid cameras. I think they are a great idea. Still sorry I didn't get one of the first all wood design, just because I like that one. But I really cannot see the reasoning behind using FR4, certainly not in its unclad version.

Oh BTW, if 15 is the double of 10.70, then I need a new calculator as well....

[Kiwi7475]

As someone who has designed and have produced both pcb's and metal parts as a commercial process I have done similar homework repeatedly.

I won't comment on wood as yes, that might be troublesome. But why anodising the alu and then laser engraving it? Every lensboard in alu I have seen is just painted and screen printed (if that). The Sinar one I have here is painter alu with a sticker logo! Something that can be done in the same shop compared to anodising and laser engraving which would mean transporting between shops, with each time packing and for the laser engraving, positioning as well. I can imagine that this is expensive! Just getting it through a painting tunnel and then a screen print would be far cheaper and better (fit for this purpose).

I really don't get the idea of comparing FR4 with vinyl coating which I find "cheap" to anodised and laser engraved which I find "premium".

Being honest I really like the Intrepid cameras. I think they are a great idea. Still sorry I didn't get one of the first all wood design, just because I like that one. But I really cannot see the reasoning behind using FR4, certainly not in its unclad version.

Oh BTW, if 15 is the double of 10.70, then I need a new calculator as well....


Sometimes we just read too fast. He wrote "Their aluminum prices are twice that for the same thickness in aluminum sheet, and around $15 /sq. ft. for aluminum plate."
So he's comparing 3 items: FR4, aluminum sheet, and aluminum plate. The sheets is 2X ~ $21.40, the plate is $15.

[Kiwi7475]

The camera is compatible with Sinar lens boards, which are very common. Critics have had their say. Why not leave it at that? If not, the end result will likely be another manufacturer who won't post here.

I tend to agree that we're beating a dead horse and this thread should now be closed by the moderators.

[Jody_S]

I really do appreciate everyones opinions on this but FR4 is a great choice for our lens boards I will explain why,

Aluminium boards = Cutting (water jet or laser) + Deburring + Tumbling or Linishing + Anodising + Laser engraving our logo + high shipping cost when done at our scale = surprisingly high cost of lens board

Wood boards = it's very hard to find 2mm thick wood that can be easily held down and cut. making the 100s of boards we need each month would be impracticle

FR4 = board arrives all ready duburred, finished in black and with logo on it as this is all part of standard pre existing product manufacturing process (PCBs) they are excellent quality light weight and work just as well as any other material we have used.

We used to make boards out of aluminium using the method above, it was a pain. I wouldn't even bother trying to make them out of wood. Work holding 2mm wood is nightmare inducing. I know lots of people on here have all sorts of experience in a range of fields but as someone who has had to make literally tens of thousands of lens boards over the last 6 years the FR4 process is miles better than anything else we have tried, and we have tried all sorts! maybe its not your cup of tea but they make for great lens boards and the whole production process is so simple we would never look back.

if you are still not sure then we will have to just agree to disagree :p

- Max

I completely agree with this and see no reason to avoid FR4 as being somehow risky or failure-prone. It's easy to throw words like that around until you're the one responsible for making a product to spec and to cost, and then suddenly words like 'deburring' and 'anodising' give you nightmares.

[jnantz]

Translucent board?? How does something like that go into production without testing?

sometimes stuff happens. not sure if you remember but a few years ago toyo had dark slides that were giving them problems.
we're living in 1900 all over again, seems mistakes will be made as we all trek forward.

[Tin Can]

backwards to future


sometimes stuff happens. not sure if you remember but a few years ago toyo had dark slides that were giving them problems.
we're living in 1900 all over again, seems mistakes will be made as we all trek forward.

[Tracy Storer]

Oh. My. God. THAT is inexcusable. For SHAME Intrepid "Camera" Co.

Unbelievably, the lens board appears to be the problem. It is a genuine Intrepid lensboard and it isn't lightproof. I put a flashlight up against the lensboard and it just shines through. 208383
It sure looked light proof. I'm aghast. I will let Intrepid know about this.

[Vaughn]

Tracey -- the manufacturer explained this in an earlier post on this thread:


Hello, I believe Naomi has all ready spoken to you about this but I just wanted to personally apologise that you received a faulty lens board, they are supposed to have a rubberised light proof backing (similar material to our bellows) and the ones you received did not have the backing applied. I'm really sorry this wasn't spotted before they were sent out. We have been through all our current stock of lens boards and can confirm they are all light proof. We will have some replacement boards on the way to you tomorrow and more than happy to add in a box of film to make up for the lost sheets.

Shit happens.

[Max Grew]

Oh. My. God. THAT is inexcusable. For SHAME Intrepid "Camera" Co.

Hi Tracy, this was an isolated problem and dealt with many months ago, not really sure why its popping back up

Thanks, Max