oh dear, I bought a 645... advice? - Page 3

*hinman* · 09-03-2009, 07:53 PM

My copy of 645N arrived yesterday. The previous owner is a female and she packed quite nice for the camera. All are working good once battery is in

Pentax 645N Purchase
shots taken with DA 35mm f/2.8 limited

Pentax 645N Purchase

*Andi Lo* · 09-03-2009, 10:29 PM

Pretty... I miss my 645N.

btw I would suggest using a normal alkaline instead of eneloops, if only because they seem to last very long on film cameras and you can use the eneloops on something else.

rparmar · 09-04-2009, 05:17 AM

Nice shots Hin! looks like a great copy of the camera. I await mine still.

D W · 09-04-2009, 07:55 AM

Originally Posted by Andi Lo

Pretty... I miss my 645N.

btw I would suggest using a normal alkaline instead of eneloops, if only because they seem to last very long on film cameras and you can use the eneloops on something else.

Totally agree. There is a noticeable AF speed difference when using longer lens like AF300/4EDIF with all that mass the motor has to move to focus. A set of alkalines last over 500 rolls of film. Don't forget you are no longer chimping which uses a lot of battery power

rparmar · 09-07-2009, 07:14 PM

So my 645N arrived and I set about documenting it in this thread. Here's my favourite shot.

Pentax 645N profile view

It came with four film backs instead of the two I was expecting, but only one is for 120, so I will sell off the rest I think. I got the standard lens but think the 150/2.8 will be my plaything.

Walking around the house with this makes me feel like an astronaut. All I need is a silver suit and a moon buggy. The cats are going to have to get used to this shutter sound.

Nesster · 09-08-2009, 07:09 AM

It came with four film backs instead of the two I was expecting, but only one is for 120, so I will sell off the rest I think.

I've looked at the 120 and 220, and searched online. Though opinions differ, I can't see any difference between the inserts, save the screwed-in metal thing in the middle. On one there's a tongue that sticks backwards, on the other the same piece is screwed in the other way, the tongue is against a wall pointing forwards. My thinking is that the two inserts are indeed identical save for this, which acts as a sensor for the camera to do the end wind after 15 or 30 exposures. Unscrewing this bit and screwing it back the other way will make the 220 back act like a 120 back.

rparmar · 09-08-2009, 04:04 PM

Hey Nesster, I was just reading about that on photo.net. I think there must also be a difference in the registration distance, but this might not be noticeable for most shots. You'd need pretty incredibly small DOF for that to matter. I am not sure how small though. I'll be sometimes shooting at f/2.8 with the 150mm... wonder if that will matter.

P67 · 09-08-2009, 10:47 PM

Originally Posted by rparmar

He he he.... well, I am already thinking of developing B&W because no-one else will, apparently. Will look into getting a changing bag and developing tank so I don't have to light-proof anything. The biggest issue might be buying a decent scanner, since I have no money for this.

But I don't think my k-mount gear will collect anything but more great photos. The 645 is a supplement, not a replacement.

The last statement lit up a big smile for me. Then I read you last post showing the photo of a special camera. Slowly, but surely the lure of MF is drawing you in. The appeal of that 645 is intoxicating.

Once your eye becomes accustomed to the larger format, and then seeing the results on an enlargement - well. I'm sure future posts from you will describe what most of us have already been through. I love my OM-1's, and one will usually ride with me when I'm kicking around or driving errands.

But if I'm going out for a "look about" for serious photography - I only reach for my 67's. I carry two bodies. One with Acros 100 - the other with Ektar 100. Spectacular films. If you get a chance to shoot the Ektar - try it at ISO 64.

I believe it's too late for you already.

Nesster · 09-09-2009, 05:30 AM

I think there must also be a difference in the registration distance, but this might not be noticeable for most shots. You'd need pretty incredibly small DOF for that to matter.

Actually if you think about it - there is absolutely no difference in registration distance - the film is pressed against the film rails, flat, in the focal plane. The difference, if any, might be in the spring tension on the back plate that presses the film to the rails.

rparmar · 09-09-2009, 05:43 AM

Originally Posted by P67

I believe it's too late for you already.

Except I cannot actually afford to buy and process film at the same rate I take digital. And I rarely make prints. though when I do I expect the best!

But we shall see.

rparmar · 09-09-2009, 05:45 AM

Originally Posted by Nesster

Actually if you think about it - there is absolutely no difference in registration distance - the film is pressed against the film rails, flat, in the focal plane. The difference, if any, might be in the spring tension on the back plate that presses the film to the rails.

Yes, that makes more sense. Now I've had a good look at a film back I agree. I have adapted a 220 for 120 film, so as soon as I actually have more than one roll of film (ha!) I will see.

*pacerr* · 11-06-2009, 09:29 PM

Originally Posted by Nesster

Actually if you think about it - there is absolutely no difference in registration distance - the film is pressed against the film rails, flat, in the focal plane. The difference, if any, might be in the spring tension on the back plate that presses the film to the rails.

Almost right. The real answer has to do with the fact that 120 film has the paper backer behind the film as it passes the backing plate; it's thicker. With 220 film, the paper ends as the film begins - i.e., the paper lead and tail is taped to the ends of the film. Consider that they must get twice as much film on the same size spool so the paper ends where the film begins.

It's this thickness that accounts for the difference in the back plate dimensions. Given that every manufacturer provides both film holders there must be a good reason.

I'm going back about 35 years to Mamiya 6x6 TLRs and something may have changed since, but that's how I learned it. As I recall, cheatin' on film holders caused the same sort of frustration as auto focus issues do today.

H2

I just thought to Google "220 film thickness" and found this is a common question for people new to ML film.