Omega D3 + Componon-s 150mm + ring of light problem

[zone]

Hallo...

I've got an enlarger Omega D3 with head dichroic.

No problem with format until 6x7 .

I bought a shredder schneider-s 150mm for negative 4x5 and there are two problems.
-It focus only with a projected format 30x40
but I solved the problem buying the bellows focus attachment instead of the cone of 5'' and 1/4

-When I project the negative in the base there is a 'ring of light' on the edge that cause a vignette.

I tried in this forum and in the net, but I couldn't find a solution.

I read in a post that you have to adjust the distance between the negative and the head of the enlarger or the mixing box, but you can't, because there are not adjustments .

After I also red that the rail of the auto focus has to be 'perfectly' coupled with the lent.
So I look at it and there are 3 plates: Rodagon 50mm…Rodagon 105mm … and Rodagon 150mm.

So I tried with different lenses (75mm Rogonar… 105mm Galileo) coupled with the rails but I still got the problem with the componon-s 150mm projected 4x5 negative.

It seems that the up bellows ( to take off the 'ring of light') should be extended, but is not possible because is on the maximum length.
So I had a look on the characteristics of the Rodagon and the Componon-s; it seems that the Rodagon has got a cover and a draw more suitable with my Omega D3, so I thought that changing the lens could solve the problem.

1 Is anyone using, or have used the Omega D3 with the componon 150mm?
2 Do you have a solution for this problem?
3 Is possible that the Componon-s 150mm (look at the link below) doesn't cover the 4x5 format? Or that anyway is not coupled with the Omega D3?
4 Eventually do you advise me with a Rodagon 150mm or a 135mm??



Rodagon's characteristics:
http://www.rodenstock-photo.com/mediabase/original/e_Rodenstock_Printing_CCD_43-62__8230.pdf
(pag 51)

Componon-s 150mm characteristics:
http://www.schneiderkreuznach.com/pdf/foto/vergroesserung_e.pdf
"recommended negative size: 90x120 mm" ????

Best regards


7804178042

78044

[ic-racer]

The 150mm focus rail should work with that lens as you are doing.

I have not heard of using the accessory bellows in place of the 5 1/4" cone to make an enlargement but I suspect that is causing the ring of light and also blocking the image of the negative. Any lens is just projecting an image of what ever is up there. Just take the lens off and look up there, you will see what is going on. It should be a better view than the dim projection.

I don't understand what you mean with this statement:

-It focus only with a projected format 30x40

The accessory bellows is for making very small prints and reductions. You may need to prop your easel up on some boxes. The paper should be closer to the lens than the negative to make a reduction or small print.

If you are doing enlargements I think all of your problems will be solved with a 5 1/4" cone. Here is one on USA Ebay, you might want to snatch that up for $20 USD: http://www.ebay.com/itm/OMEGA-5-25-LENSMOUNT-421-155-FOR-150MM-LENS-ON-D3-OR-D4-ENLARGER-/221051506412?pt=LH_DefaultDomain_0&hash=item3377b24eec#ht_500wt_1249

KHB lists the 421-1555¼" Cone for 150mm lenses as "Current Production" and available, but that web page may not be up-to-date.

[alex villegas]

I don't know if it helps, but i have a D2V and the Componon-S 150mm... works fine.

[zone]

Hallo ic-racer...

I bought the bellows focus attachement because I thought: why buy a cone for each lens? with a bellow can adjust all the focal range!
Perhaps wrong. But... i've read on user manual and literature about a reduction questions, my english is not perfect so maybe I do not understand; so 1+1=2 (cone or bellows=adjust the distance of the lens from the negative carrier). I do not know if I have explained.




I don't understand what you mean with this statement:

-It focus only with a projected format 30x40


When I bought the enlarger I had not all the necessary information, only the base information for an "normal" (:) ) enlarger. This enlarger was supplied with only a unspecified cone (no label on the cone), one lensboard and also problems of alignment and power supply (the Italian standard voltage is 220v) The price was really good and I wanted to print my negatives soon. With this minimal equipment I could focus only about 30x40 or 40x50.

I have seen the link for the auction, it looks interesting, I hope they the seller send in Italy.


So if I understand correctly, your opinion is that the cone has to work, even if the rail shall be marked rodagon 150mm?

Thanks for your time.
Enzo.

[zone]

I don't know if it helps, but i have a D2V and the Componon-S 150mm... works fine.

Hallo alex villegas
I don't know D2V, maybe is not autofocus ... thanks, everything is appreciated at this time.

[ic-racer]

So if I understand correctly, your opinion is that the cone has to work, even if the rail shall be marked rodagon 150mm?

.

Yes. I think you should try to see if you can get that cone on ebay. $20 usd is cheap for that cone even if shipping is an additional $35. That cone is the only way to use the enlarger with a 150mm lens.

I think I know what it is like for you, in Italy, to fix up a USA Omega as I have spent a lot of time here in USA fixing up my Italian Durst!

[goodfood]

Make sure you color head comes with a 4X5 light mixing chamber DD, not a medium format DB.

[zone]

thanks goodfood, i've checked because i've tought perhaps the mixing chamber for 2,25x3,25 or 3,25x4,25 or other strange format... yes, strange things about me...
mixing chamber is 4x5 negatives.

I followed the advice of ic-racer.... i bought the 5,1/4'' cone.. now, i hope just that post service does a good job...

stay tuned for the next "develop"

[ic-racer]

zone, do you have the manual? If not here is a PDF (in English): http://www.jollinger.com/photo/cam-coll/manuals/enlargers/omega/OmegaD3andD5.pdf

[zone]

thank Ic-Racer...I had already printed this book, I'm wondering why I can not find the size of the cones in optics. What would you use for cone 105 and for 80 and 50 mm?
If I can just use a enlarger for all formats, it will sell one in order to gain more space, although I often read that many people use two magnifiers, there is a real enhancement using two enlargers, only one for GF?

[Captain_joe6]

The key point to consider is that in an autofocus system, all values must remain known and constant in order for the autofocus function to function. With the accessory bellows, if your lens is misplaced by even a fraction of a millimeter, your focus will be off. What you need is a lens cone for each different lens, and a focusing cam rail for each. To fit the 150mm lens, you'll be after the 5 1/4 (~133mm) lens cone.

[rdenney]

Check and make sure you have a focus track that is marked for something close to 150mm. Unless you really want to preserve accurate focus as you change magnification, it does not have to be exact. But the track follower provides the base position for the lens stage. If the track follower is not present or not close to correct, the focuser will be working out of range with the possibility of vignetting or producing unexpected reflections that cause things like that ring. Or you may not be able to focus it at all.

The proper cone is part of the track design. The longer the lens, the longer the cone. 150mm uses that 5+" cone. The 139mm I used required a 4-3/4" cone, or something like that. I made a 3" cone for the 80mm lens I used for 6x6, etc. I also made a track for that lens by cutting some sheet metal and riveting it to a track for a lens I don't use (but that came on the enlarger that I bought used about 30 years ago). The D3 holds three tracks.

Again, it does not have to be precise unless you really want it to stay focused as you raise and lower the head. That was not a requirement for me. I just wanted the lens to be positioned within the range of the stock focuser.

Rick "who had to figure out the D3 mechanics by reverse engineering" Denney

[lenser]

Good afternoon, Zone. Assuming that this web site is still up to date, active, and that the original owner is still with us, I was able to find some very obscure Omega information from him about two years ago if my memory is correct. He seems to be an incredible resource for info on all things Simmons-Omega. www.khbphotografix.com/omega

Hopefully he will be able to resolve you problems.

Tim

[zone]

Good news...
i've purchased the cone linked from Ic-Racer. Today the post-office has delivered the cone, and i take first test. The componon 150 work fine matched with cone and work fine the autofocus system.
Thanks Ic racer... and thanks at all for the contribute.
So following rdenney reasoning i've need of 3" cone for 80mm and which cone for 105 mm????




The proper cone is part of the track design. The longer the lens, the longer the cone. 150mm uses that 5+" cone. The 139mm I used required a 4-3/4" cone, or something like that. I made a 3" cone for the 80mm lens I used for 6x6, etc. I also made a track for that lens by cutting some sheet metal and riveting it to a track for a lens I don't use (but that came on the enlarger that I bought used about 30 years ago)

[rdenney]

So following rdenney reasoning i've need of 3" cone for 80mm and which cone for 105 mm????

According to http://www.khbphotografix.com/omega/, which was provided above, you need a 1-1/2" cone for 80 and a 2-1/2" cone for 105.

Again, these do not need to be exact unless you expect the autofocus system to work precisely. I suspect my homemade cone for an 80mm enlarging lens is close to 3", but then the autofocus track for that lens is homemade, too. If you have a track already designed for 80 and 105mm lenses, then use the cones shown in the web page.

I probably would have preferred a D2, but I got my D3 back in the day when even used Omega enlargers were expensive, and that was the deal that came my way.

Rick "who keeps that enlarger for some odd reason" Denney