Why different rise lengths for Sinar F2 rear standards?

[digital_archivist]

I have two different rear standards for which I believe are for a Sinar F2. As you can see from the photo below, one has much longer posts than the other. What's the difference between these two standards?

 

[abruzzi]

the front standard of a 8x10 needs more rise than the front standard of a 4x5. Its possible that the standard, or parts off the standard, were from a larger format model F2.

 

[digital_archivist]

That makes sense - thanks. I'll have to check the catalogs and see if I can confirm.

 

[reddesert]

I believe that on the Sinar F2, the front and rear standards are almost exactly the same. Meaning that although these look like two rear standards, one of them could be a front. It's on the F and F1 that the front standard is a little simpler and lacks some features (although they are all compatible).

In this screenshot from a Sinar F2 brochure, in the top picture of the 4x5, the parts 431.61 and 431.66 are the 4x5 front and rear standards. In the lower picture of the 5x7, 431.62 is the front standard to be used for 5x7 and 8x10, close to the same thing with longer posts.

 

[digital_archivist]

Thank you. I'll take a second look at the standards and see if one is really a front.

 

[DREW WILEY]

Not exactly. Actual F2 8x10 risers are supposed to be not only longer, but thicker and made of steel for maximum rigidity. In the case of F2 4X5 risers being much longer than previous F model rods, I suspect it's just a matter of accommodating potentially extreme rise movements. I found their sheer length annoying in terms of portability, so sawed them back down to the more typical length, which is plenty long for just about any 4x5 application I can think of. Might potentially make sense with 5x7 format, however, or perhaps a bootleg 8x10 conversion.

 

[digital_archivist]

Good points; also, after a second look, I'm pretty sure both are rear standards. I'll probably just use the shorter version in the rear and swap out the other for a proper front standard.

Thanks again for the responses.

 

[abruzzi]

the F2 should have a full focusing front standard, very similar to the rear. The easiest way to determine if its a front or rear is the location of the knobs. the focusing knobs should be on the right side.

 

[DREW WILEY]

F2 front also has independent swing and shift locks, whereas on the previous F standards, it was combined.

 

[abruzzi]

I was looking at your first photo of the F2 upside down. The standard pon the left in the photo has a small knob facing us and centimeter markings on side of the rail clamp. If you look at photos of F2s online that seems to be the usual rear standard, for instance here:

https://www.districtcamera.com/cdn/shop/files/190251_1.jpg?v=1727715431&width=5760

The front standard focuses but it doesn't have that knob (I don't know what that knob does.) But that extra knob should be on the opposite side of the focusing knobs on both front and back (you can see both focusing knobs in the picture I linked.) But going back to your picture--that knob is on the same side as as the focusing knob on the standard on the right, meaning both are probably rear standards.

Sinar interchangability is very flexible so you could setup a system with both front standards or both back standards, but they are different. And if you know what you're looking at, you can go through ebay listings and see that a quarter of the cameras are bodged together from parts. Most comonly you'll see cameras listed as F2 but that have the weak, non-focusing F standard in front.

A few years ago I bought a 5x7 Sinar Norma, and had this exact problem. The seller had cobbled the system together, and I wasn't knowledgable enough at the time to realize what had been done, so I had a Norma with 2 front standards. I was able to eventually fix it by buying the correct rear rail mount and move the 5x7 frame to that. But intil then I just had to deal with the focus knobs on opposite sides.

 

[digital_archivist]

As you can see, I flipped the 'front' standard around so the shift lock was facing the front. Both standards seem to be identical save for the length of the rails.

I've purchased a proper front standard from someone here in the forums; I hope to try it out this weekend.

Thanks once again to everyone who replied.