Super Chromega D Dichroic II Image Size Issue

[Jebbur]

I've owned a Chromega D once 25 years prior and never had an issue with image sizing. I was also in high school and unfortunately lost all my equipment due to hurricane Katrina. With that said, I purchased another Chromega D and now experiencing issues getting the projected image enlarged greater than a 8x10 print. I don't ever remember being maxed out to 8x10 prints previously. I recall being able to print up 20 x 24. However this is a new enlarger. I raised the enlarger head to the top of the column and decreased the bellows as far as they could go and still can only get to an 8x10 print. I am attempting to print from 35 mm negatives and have three lenses at my disposal (all Fujinon lenses). The lenses are a 3.5/50mm, 5.6/90mm, and 4.5/105. The first two lenses dont enlarge the image at all. The 4.5/105 is the one lense where I can get the image to an 8x10.

I am wondering if I need a different lens outside the ones I received with the enlarger? If so, what kind of lens do I need to make a larger print from 35mm negatives? If it's not a lens issue, what else could be the problem? Your help is appreciated.

PS Its the Chromega E model.

 

[MattKing]

Welcome to Photrio.
We need some more information
"Super Chromega D Dichroic II" describes only the light source on your enlarger, not the enlarger itself.
Perhaps the KHB index of enlarger types will help you share more: http://www.khbphotografix.com/omega/Enlargers.htm

 

[MattKing]

PS Its the Chromega E model.

Which lens cone?
http://www.khbphotografix.com/omega/Enlargers/ChromegaE.htm

 

[koraks]

I am wondering if I need a different lens outside the ones I received with the enlarger?

No, but most of the larger enlargers require a recessed lens board with shorter focal length lenses, otherwise you're limited in the degree of enlargement and/or can't focus at all.

 

[Ian C]

You need each lens mounted on the proper lens mount to place the lens at the correct distance to attain focus over the range of magnifications for which the enlarger was designed.

The Chromega E can use lenses of 50 mm through 210 mm per the data on the KHB Photographix site. The image of the Chromega E on the KHB site shows the machine with a long lens mounted on a square lens cone for 5” x 7” enlarging.

http://www.khbphotografix.com/omega/Enlargers/ChromegaE.htm

In your list of lenses: 50 mm/3.5, 90 mm/5.6, and 105 mm/4.5, only the 50 mm lens is appropriate for engaging the 35 mm format.

The lens is first attached to the appropriate lens disc. Then the disc & lens is attached to the mount. The proper mount for a 50 mm lens according to the KHB data is the 421-1 Flat Mount for 50-90mm lenses.

The 90 mm lens is intended for medium format negatives of 6 x 7 cm, but can be used for 6 x 4.5 cm or 6 x 6 cm.

The 105 mm lens is best used for 6 x 9 cm negatives but can be used for smaller medium format negatives as well (with less magnification than the 90 mm).

 

[MattKing]

What Ian C posted, with the additional qualification that you need to use the right lens disc with the right lens cone - together they constitute the appropriate lens mount.

 

[Doremus Scudder]

Just to clarify: Omega E enlargers are 5x7 enlargers; D enlargers are 4x5 enlargers. Chromega is the color head; again, D is for the 4x5 head, E, for the 5x7 head.

Do make sure which enlarger chassis you have and which color head (a D head on an E enlarger might be problematic, but maybe okay if you're only enlarging smaller negatives). Also, be aware that there are film-format-specific light mixing boxes for the color heads. You can enlarge smaller negatives with a mixing box designed for larger ones (with less efficiency do to light loss), but not vice-versa, since there will be no coverage.

Basic optics about lens-to-negative and lens-to-baseboard distances apply here. If you can't focus your image on the baseboard, you need to change the lens-to-negative distance to compensate (cone or recessed board or whatever depending on the nature of the problem).

The Omega enlarger system, especially for the older enlargers, included lots of things to space the lens correctly in relation to the negative depending on format. A bit of research will help you understand the ins and outs.

Have fun,

Doremus

 

[koraks]

the right lens disc with the right lens cone

Thanks; sorry for creating confusion by mentioning recessed lens boards. I wasn't aware that this enlarger solves the issue in the opposite way - by mounting the longer lenses on cones instead of mounting the shorter lenses on a recessed board. I'm familiar with the Durst approach, which is the latter.

 

[Sirius Glass]

Welcome to Photrio. It sound like the enlarger needs to be leveled and aligned. Also you need the proper length len for each film size. Contact http://www.khbphotografix.com/omega/Enlargers/ChromegaE.htm for advice.

 

[koraks]

It sound like the enlarger needs to be leveled and aligned

Not really. It just needs the proper lens mount, that's all.

 

[ic-racer]

Can you post a picture of the enlarger and how you are mounting the 50mm lens. Thank you.