Pentax 645 underexposing and light leak

[pentax_user_645]

Hello Photrio,
I bought a P645 a couple of months ago and have shot a few rolls on it now. My issue is all my shots are underexposed by about 2 stops and I am getting what looks like a light leak issue. I used the sunny16 rule and also used an external spot meter. I've been shooting film for 5 years now so I know what I am doing. Please let me know if the photos attached are helpful. The first geese photo is it scanned at 0 exposure on SilverFast and the next same geese photo is when I added 3 (stops?) of exposure when scanning. The lines are only on frames 8, 11,12, and 13.

 

[ic-racer]

Can you send it back?

 

[mklw1954]

I have the original manual focus P645. A few things to check. Film: are you sure your film is not underdeveloped? Meter: does the meter correlate pretty closely to Sunny 16? Lens(es): check your lens aperture blades to see if they open sluggishly or incompletely (oil on the blades?), or if they snap open and closed quickly. If you have more than one lens, is underexposure occurring with all of them?

Light leak: likely caused by a bad film holder seal. The holders have very thin foam around the inside perimeter of the holder, none on the camera body. Is the film holder tightly securing on the body?

 

[Hassasin]

Using P645 with "sunny 16" is an odd way of using such a capable camera. Try Auto mode before assuming frames ae underexposed. Every frame you show here would have been well exposed with built-In metering without any adjustments/compensation. Provided processing is fine.

The "light leak" is likely from scanning.

 

[pentaxuser]

Have you tried the checks suggested in #3 and if so what if anything did you find?Oh and can we take it that you did your own processing? Even if you didn't can you show us digital pictures of the actual negatives A negative can tell us a lot

pentaxuser

 

[Pioneer]

I hope you were able to work it out. That Pentax has an absolutely awesome metering system. Go out and compare your Sunny 16 estimates with the camera's meter readings? Were the underexposed frames backlit?

Pick up a second film back, they are usually inexpensive, and see if the light leak is related to the back. I have occasionally experienced some light leaks thru the outside edges on 120 roll film when I left a roll sitting in the sun or other bright light for a long period.

 

[GregY]

Hello Photrio,
I bought a P645 a couple of months ago and have shot a few rolls on it now. My issue is all my shots are underexposed by about 2 stops and I am getting what looks like a light leak issue. I used the sunny16 rule and also used an external spot meter. I've been shooting film for 5 years now so I know what I am doing. Please let me know if the photos attached are helpful. The first geese photo is it scanned at 0 exposure on SilverFast and the next same geese photo is when I added 3 (stops?) of exposure when scanning. The lines are only on frames 8, 11,12, and 13.

Are the photos on all rolls "under exposed"? I'd do a complete test with a roll or two. Make sure you're using fresh batteries. Check the seating of the film insert/back. Check to make sure you're using the controls. (lens set to A when using programme modes). Run through all the speeds. As mentioned check the lens diaphram... for oil and smooth operation. The Pentax 645 is a great camera w fine lenses..... but it's not all that simple (that's my opinion from years of using Leica RF/ Rolleiflex/ & Large format). Definitely worth reading through the manual which can be found online. Hope you get the issues cleared up. I like mine a lot!

 

[wiltw]

Hello Photrio,
I bought a P645 a couple of months ago and have shot a few rolls on it now. My issue is all my shots are underexposed by about 2 stops and I am getting what looks like a light leak issue. I used the sunny16 rule and also used an external spot meter. I've been shooting film for 5 years now so I know what I am doing. Please let me know if the photos attached are helpful. The first geese photo is it scanned at 0 exposure on SilverFast and the next same geese photo is when I added 3 (stops?) of exposure when scanning. The lines are only on frames 8, 11,12, and 13.

Just to make sure we are all understanding the background use...

1. Are you using Sunny 16 and/or external Spot meter to determine what settings to have, and the camera underexposes with those settings? or
2. Are you using Sunny 16 and/or external Spot meter to determine what settings apply, and you compare those settings to the Pentax 645 meter which indicates less exposure?

Your linked photos are underexposed...do these represent the fact that even using Sunny 16 rule of thumb (or Spot meter) the resultant shots came out underexposed, as shownm (response #1)?
If so, Sunny 16 should give you reasonable exposure (although many times Sunny 16 is really f/16 + 0.5EV -- or even more!), and that would seem to indicate something wrong with shutter or aperture.

If response #2, your Pentax 645 meter would seem to need calibration.

 

[mklw1954]

On the light leak, I suggested checking the foam seals in the film holder. I see that USCamera sells replacement seals for P645 film holders that you should be able to replace yourself with the help of their instructions.