converting graflex rb super 3 1/4" x 4 1/4" to 4" x 5"

[pablogustav]

sheet developing

Thank you Roger and Rawhead,

Thanks for all help and advice. To update; I recently went to my photo finisher around the corner from me and was told they will no longer handle my 3 1/4" x 4 1/4" negs anymore....so, I went to my other option on the other end of town and dropped off my 12 sheets to them from my magbag. Their fee is 4.50 per sheet. They are a great shop that is keeping film alive, but I realized I definitely do not want to be spending that amount for every sheet. The counter person understood my dilemma and as many people have advised, he showed me a Patterson tank with an adjustable frame that I can load my sheets into for developing. For $40 it seems like the obvious way to go. Before I purchase it, I just wanted to see if that is a good standard tank that most people use or should I be considering another brand? Also, I am following Rawhead's advice and looking out for an old beater RB that I can scavenge the 4 x 5 rotating back off of to install on the smaller Graflex, but for now, I want to give developing it myself a try. Here is the last photo I took with the RB series B 4 x 5; these cameras are really a hoot!

 

[k_jupiter]

Thank you Roger and Rawhead,

Thanks for all help and advice. To update; I recently went to my photo finisher around the corner from me and was told they will no longer handle my 3 1/4" x 4 1/4" negs anymore....so, I went to my other option on the other end of town and dropped off my 12 sheets to them from my magbag. Their fee is 4.50 per sheet. They are a great shop that is keeping film alive, but I realized I definitely do not want to be spending that amount for every sheet. The counter person understood my dilemma and as many people have advised, he showed me a Patterson tank with an adjustable frame that I can load my sheets into for developing. For $40 it seems like the obvious way to go. Before I purchase it, I just wanted to see if that is a good standard tank that most people use or should I be considering another brand? Also, I am following Rawhead's advice and looking out for an old beater RB that I can scavenge the 4 x 5 rotating back off of to install on the smaller Graflex, but for now, I want to give developing it myself a try. Here is the last photo I took with the RB series B 4 x 5; these cameras are really a hoot!

A Patterson tank with an adjustable frame for 3.25x4.25??
News to me.

I use the Patterson System 4 tank with handmade nylon screen tubes that you fit the film in (Emulsion to the inside). You get 4 or 5 tubes per load. Develop just like 135 film. The other solution is with fluorescent tube protectors cut to length, but then you have an additional step of washing the anti-halation film off the back when you are finished processing.

Good luck. You will find processing your own give infinitely more control over your whole process.

tim in san jose

 

[rawhead]

Here you go; got the conversion plate from Bert a couple days ago, finally found the time to do the conversion. Took all of 35 minutes. 100% reversible.

Only issue at the moment is that there's a focus calibration issue, and I may have to adjust the top ground glass to coincide with the rear focal plane.

It covers a pretty big chunk of a 4x5 Fuji Instant film. Need to check with 3x4 Instant as well as 4x5 film, coming soon

 

[shutterfinger]

1. Bert's got 20 years on me.
2. A standard film holder backing plate is .197 ± .007 from the film holder edge for formats 2x3 through 4x5.
http://home.earthlink.net/~eahoo/page8/filmhold.html
3. A Graflex film holder backing plate is .224 from the film holder edge in 4x5, tolerance unknown.
4. The view hood ground glass can be shimmed up to 1/8 inch (.125) higher without causing problems, lowering more than .010 inch may require milling the mount opening down.
5. TriX TXP sheet film is .007 inch thick.

 

[k_jupiter]

1. Bert's got 20 years on me.
2. A standard film holder backing plate is .197 ± .007 from the film holder edge for formats 2x3 through 4x5.
http://home.earthlink.net/~eahoo/page8/filmhold.html
3. A Graflex film holder backing plate is .224 from the film holder edge in 4x5, tolerance unknown.
4. The view hood ground glass can be shimmed up to 1/8 inch (.125) higher without causing problems, lowering more than .010 inch may require milling the mount opening down.
5. TriX TXP sheet film is .007 inch thick.

What is the delta difference between the base of the Gralex mount and the Graflok mount to the same point within the camera body? The math states you have 0.015 to 0.150 to play with, yes?

tim in san jose

 

[shutterfinger]

The standard film holder places the film closer to the lens making the image out of focus when used on a camera whose ground glass is set for the Graflex film plane. This is the reason the Graflex SLR view hood ground glass has to be repositioned when converting the camera from using Graflex film holders to using standard film holders even if the back is replaced and mounted in the same position as the original.

 

[k_jupiter]

So you are saying the old back plate and the new back plate are the same thickness?

 

[shutterfinger]

I've only done 2 mods, converted a 1910 RB Auto to use standard film holders then switched it back when I sold it; Made an adapter for a 3x4 RB Auto to hold a Graphic roll film holder. In both cases the original back frame was used.

 

[mhcfires]

I have two 6x9 roll film holders for my 3x4 Model D SLR. If push comes to shove on sheet film, I can always shoot 120. I have plenty of green sensitive x-ray film, I'm going to try cutting it and loading into a bag-mag. Converting it looks to be too much of a PITA.

m

 

[rawhead]

Don't quite understand why you think it's a PITA, when it's been noted several times in this thread, and confirmed by me, that the conversion takes less than 30 minutes, and is 100% reversible.

Now, cutting down *any* sized film down to 3x4 for each and very frame in a darkroom, or even under safe-lights... now THAT is a PITA But I guess to each his own. I'll enjoy shooting stock 4x5 sheet film and 4x5 as well as 3x4 Fuji/Polaroid instant film on my converted R.B.

 

[k_jupiter]

I've only done 2 mods, converted a 1910 RB Auto to use standard film holders then switched it back when I sold it; Made an adapter for a 3x4 RB Auto to hold a Graphic roll film holder. In both cases the original back frame was used.

Ok, so a different modification is talked about then.