Should I replace a broken mixing chamber IR filter?

[AndreiR]

Hello forum members!

I'm new to this forum. I just bought my first 4x5 enlarger, an Omega Super Chromega D Dichroic II enlarger. It looks like it came with everything needed to start working with it. It even came with a Minolta Color Translator DMT II attached. I'm not planning to do color prints, so I decided to remove the sensor from the mixing chamber. That's when I discovered that the IR filter of the mixing chamber is severely cracked. My question is: Is it critical to replace that IR filter? I found one on eBay for $38 plus shipping.

I must add for clarity that photography is my hobby, and I'm not planning to do high volume printing.

Thank you, and I look forward to learning more about large format photography.

[esearing]

If you found one buy it. You won't be able to find it in the future when you decide you need it. If you give up the hobby then the next person inherits your good/bad maintenance of the equipment.

[ic-racer]

What problem is the crack causing?

[xkaes]

Can you provide a picture? Is the "crack" a straight line? If so, then it's meant to be there.

[AndreiR]

If you found one buy it. You won't be able to find it in the future when you decide you need it. If you give up the hobby then the next person inherits your good/bad maintenance of the equipment.
Thank you, esearing! That's a good thought.


What problem is the crack causing?
I guess it doesn't provide an adequate protection to the foam lining of the chamber.


Can you provide a picture? Is the "crack" a straight line? If so, then it's meant to be there.
Unfortunately it's a real crack.
250371

[AndreiR]

I decided to do "the right thing". I found one on eBay, and placed the order. $47.16 total with shipping. ;)

[Mark Sampson]

That's doing it right. Despite my decades of using those enlargers, many of them in fact, i've never seen that failure.
Who knows how an IR leak would affect the color balance of your prints? Perhaps less of a problem in b/w than in color, but it's one less thing to worry about.

[AndreiR]

That's doing it right. Despite my decades of using those enlargers, many of them in fact, i've never seen that failure.
Who knows how an IR leak would affect the color balance of your prints? Perhaps less of a problem in b/w than in color, but it's one less thing to worry about.

I also was puzzled -- how in the world would it crack!? Perhaps from the accessive heat? That's my only guess.

I doubt that crack would affect the B/W printing. But here is the blurb from the site that actually still sells those filters -- khbphotografix.com:

Another item that may occasionally need replacement on Omega Super Chromega C, D and E Dichroic enlargers is the IR filters on the side of the mixing boxes. These filters normally should last the life of the enlarger, but we do sometimes see mixing boxes with these filters broken or missing altogether. The infrared filter is necessary because it prevents the transfer of heat into the mixing box which will quickly damage the styrofoam liners. If the filter on your mixing box is missing or the glass is broken, this is the proper replacement.

So the concern really is about heat transfer, not the color.

[LabRat]

They get really hot in front of the lamp and I have even seen projector condensers crack from heat... Yes, the mixing box is lined with plastic materials...

I add them to condenser enlargers too, as this reduces IR heating to the neg in carrier resulting to less "popping" and even emulsion baking while in enlarger... Also helps cut Newton's rings in glass carriers as the film is not baked drying unevenly during focusing and exposure...

Steve K

[Doremus Scudder]

I'm wondering, if and when OEM IR filters for Chromega heads are no longer available, if a photographic IR filter would do the job. One could be cobbled into the mixing box fairly easily. If so, does anyone have an idea of the specs? 750nm or...?

Best,

Doremus

[AndreiR]

I'm wondering, if and when OEM IR filters for Chromega heads are no longer available, if a photographic IR filter would do the job. One could be cobbled into the mixing box fairly easily. If so, does anyone have an idea of the specs? 750nm or...?

Best,

Doremus

I had just exactly the same thought.