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alen
28-Jan-2016, 21:15
Hi all, I recently got my Pentax spot meter 2nd hand (at a reasonable price) and is my primary light meter. I have no problem with it when its bright, however in low light scenarios ill meter a scene and besides the brightest highlight, the shadows and darks will all meter at 0 (even though theyre different shades).

So my question is, what happens in these scenarios, what do I do? I dont want to get another modern meter, but learn to work around this going forward if there is a way.

vinny
28-Jan-2016, 21:20
Is it the digital version?
The minolta F was the best low light spot meter I ever owned but I get buy doing night work with the pentax digital. I meter whatever I can and place it on a zone. There's always something to get a reading off of but you must interpret it for what it is.

LabRat
28-Jan-2016, 21:59
I do a lot of night work, and yes, there is not much meter movement on the low range of the scale... Usually you might get a reading that just makes the threshold of any reading at all in low light (and usually for a highlight or upper midtone)...

What I do is visually define 3 low light thresholds that barely read; bright (dark, that reads on the lower ranges/steps of the scale), medium (that barely reads at all on the lowest division of the scale), and low (that does not read at all)... With some testing (and educated guesses), one could about find an exposure range for the 3 situations above that will usually work OK... For me with B/W and some color, I find that the first range (as above), +1 stop (2x) will work for the most part as the base for exposure (add other factors in after), the middle range is about +2 stops (4x) more base exposure, and the visible/very dark range (below scale) is about +3 stops (8x) on my Pentax Digital Spotmeter... This gets me into the ballpark, and experience is my guide... (YMMV!!!) Pay special attention to reciprocity/bellows factor/CC filter factors, etc. carefully and add them after your reading... Try to stay away from tiny f-stops, as these are very hard to get detail in very dark areas, and increase contrast (and can extend your exposure to over an hour easily)... And note your tests, and carry notes into your shooting situations...

Remember that there is always (at least) some light bouncing around in a night scene, and the film will start picking it sooner or later...

This should get you started...

Steve K

alen
28-Jan-2016, 22:44
Thanks gents.

Steve, that makes sense and is re-assuring going forward. Ill probably do a little bit of trial and error, color slides might actually be easier to meter for than negatives in this situation.

LabRat
29-Jan-2016, 06:12
Oh, and here's one more test...

It's very helpful to do a test for something I call "limiting exposure", which after a certain point "night" starts turning into "day" (a scene will start looking like it was shot in daylight, with the sky MUCH brighter)... If you expose for long enough, the film gets more & more sensitive as you expose, so it's good to test at what point you should close the shutter to preserve that night effect... A series of longer exposed tests should do... This will change when shooting under a clear, dark night sky, or with a hazy cloud cover... And dark, country areas and light polluted urban areas will reach the "limiting" point differently...

Testing, testing, testing....

Steve K

Chauncey Walden
29-Jan-2016, 17:37
This isn't the model with the 2 batteries, is it? One hidden underneath the other one?

alen
31-Jan-2016, 01:15
It takes four LR44 batteries or one 4LR44 battery. The exact model is Asashi Pentax Digital Spot meter, number above says 2729. Number on the bottom of the handle says 139230.

But on another note, I have another problem with the meter...

It drains battery like theres no tomorrow! I mean, I just replaced the battery 4LR44 battery with four LR44 batteries and the meter didnt last the night! It was working the day i replaced them, but the following day the meter was dead again :eek:

I mean it shouldnt behave like this right? And I should not have to remove the battery while not in use either.

What do you guys think??

RichardRitter
31-Jan-2016, 05:40
When the tiger is not pulled there is no current going to the meter.
How are you storing the meter?
Try putting new battery in and laying it on a table over night or for a few days.
The battery in my meter last about a year I use my meter almost daily.

HMG
31-Jan-2016, 08:24
Invest in a decent battery tester to make sure that of the 4 that drained overnight, it wasn't just 1 or 2. I've often found with button cells that quality varies and that 1 will fail much sooner than others from the same package or batch. Also, I find the silver oxide cells more reliable than the alkaline ones.

alen
31-Jan-2016, 15:51
When the tiger is not pulled there is no current going to the meter.
How are you storing the meter?
Try putting new battery in and laying it on a table over night or for a few days.
The battery in my meter last about a year I use my meter almost daily.

I think this is a good idea to help isolate the issue, I'll do this.
It was in my backpack but i was sure to place it in a way which wouldnt accidentally press the trigger.

Battery tester is a good idea too, though it might be a step too far for the time being :)

JerryP
31-Jan-2016, 19:39
If all else fails, send it to Richard Ritter and he will make it right. Www.lg4mat.net
He works on mine and is the authority on Pentax Spot Meters.

alen
2-Feb-2016, 15:18
Thanks Jerry, good to know I have a place to go if all else fails.

LabRat
2-Feb-2016, 19:15
Don't use the single (stacked) LR44's in your light meter, as I have found there could be slight contact issues between the batteries that could make meters have trouble... (I have a Minolta IIIf that does not like stacked cells!!!) Try to find a fresh lithium single for it, and it might be much happier...

It seems that single cells sometimes have a very slight oxidation on each surface that is not an issue when used alone, but stacked kinda compounds that slight resistance... Sometimes it will be fine, but on a damp night, my meter would hardly work... Clean each surface with a pencil eraser, or wiping with a Q-tip damp with 91% alcohol or lighter fluid will sometimes leave a very light discoloration on the tip of the swab from the oxidation, even on new cells... And someone's point of that sometimes new cells barely have the right voltage is spot on...

With the lithium cell in my Pentax digital spot, it's been over 5 years and my meter battery is still good, and used almost daily since, so if yours is eating batteries, it should be looked at (and a calibration check is never a bad idea...)

Also, when I got mine, it needed some service, and I brought it over to QLM, and George just sent it to Pentax at no charge/cost, so some addiional service options here... I'm glad I did looking back at the countless times I have used that meter... :-)

Steve K

Sal Santamaura
3-Feb-2016, 09:50
...Try to find a fresh lithium single for it...With the lithium cell in my Pentax digital spot...


...I find the silver oxide cells more reliable than the alkaline ones.Once you've got the battery depletion issue (likely an electrical problem) fixed, I strongly suggest using only a 6V silver oxide battery in your meter. See my posts on the subject in this thread:


http://www.largeformatphotography.info/forum/showthread.php?5566-Pentax-digital-spot-meter-battery-question

The highest quality version I've found that's still available is made by Varta:


http://www.freestylephoto.biz/04028-Varta-PX28-4G13-544-4SR44-6.2-volt-Silver-Oxide-Battery

They last well over a year in my Pentax digital, but I replace them annually anyway, rotating the removed one into "spare" duty.

Drew Wiley
3-Feb-2016, 09:52
I've had good luck with both Varta and Duracell (which is available more places).

Sal Santamaura
3-Feb-2016, 10:05
I've had good luck with both Varta and Duracell (which is available more places).I've not seen a silver oxide Duracell PX28 lately, only lithium and alkaline versions. Can you provide a link to one? Thanks in advance.

alen
3-Feb-2016, 18:17
You guys are awesome, really appreciate all your help with this. I've been a bit disheartened by this but I hope you have mentioned above, an issue with stacked batteries.
I have taken your feedback and ordered the single 4LR44 battery but in Alkaline version for now.

alen
11-Feb-2016, 04:20
Update for those curious or concerned, i replaced the four individual LR44 batteries with the one 4LR44 battery and all is well again. Much relief that my investment wasnt a waste and all the fuss was simply batteries. Now lets see how long it lasts...

neil poulsen
11-Feb-2016, 12:52
Is it the digital version?
The minolta F was the best low light spot meter I ever owned but I get buy doing night work with the pentax digital. I meter whatever I can and place it on a zone. There's always something to get a reading off of but you must interpret it for what it is.

Plus, the Minolta Spotmeter F takes a single 'AA' battery. I picked one up last year for $75 and sold my Pentax Digital. (I looked at that meter and saw dollar signs.)

Actually, my problem with the Pentax digital is that it only measures to the nearest 1/3rd stop. That's fine in the field, but I need finer distinctions for the testing that I do.