PDA

View Full Version : Nikkor 450mm M Question



AnzaRunner
14-Apr-2009, 08:14
I just received a used 450mm nikkor lens that is in excellent shape. I have a question to those of you who have the same lens. I am trying to find out if a certain behavior is normal.

The lens works perfectly fine, except for one particular thing that I do not know if it is a defect, or just the way the lens is designed. If I cock the shutter fully, all is fine. However, if I cock the shutter to the point where it clicks, but I don't pull the lever the additional 1mm or so to where it stops, the lever will slide back and the shutter will open. My guess is that you need to make sure you cock it until it stops so that the shutter is held in position, ready to fire. I don't think this would be a problem because I would cock the shutter before pulling the darkslide, but if for some reason the dark slide was removed, and I didn't make sure to crank the lever all the way over, I would end up exposing the film too soon.

Gem Singer
14-Apr-2009, 08:26
It's a Copal 3 shutter. It is not operating correctly. Needs servicing.

AnzaRunner
14-Apr-2009, 10:05
It's a Copal 3 shutter. It is not operating correctly. Needs servicing.

Sounds like its going back to the original owner.

Gene McCluney
14-Apr-2009, 11:23
Those Copal 3 shutters are very easy to take the front cover off and clean the innards with a non-residue spray cleaner. If you are the least bit mechanically inclined. I recently purchased a very nice used Symmar-S lens for $100 less than normal because the slow speeds on the Copal 3 were not working. Took me all of 10 minutes to correct the problem with a cleaning.

Gem Singer
14-Apr-2009, 12:49
It takes a professional repair person to do a proper CLA. Perhaps the seller would entertain the idea of paying all, or part of the cost of the service.

I checked the Copal 3 shutter on my 450M. I could repeat the problem that the OP described if I purposely did not cock the shutter all the way. However, a smooth continuous movement of the cocking lever seemed to engage a part that held the lever in the cocked position until the shutter was fired. If that part is worn, or broken, it might need to be replaced, adding to the cost of the repair.

Gene McCluney
14-Apr-2009, 13:03
While it does take a professional repair person to "calibrate" a shutter, if the problem is dried lubricant or other forms of dirt and grunge, a simple flush-cleaning as I mentioned can often solve the problem and it does not take a pro repair person to do this. If the buyer can get the seller to pay for a CLA all the better, but if he got a really really good deal on the lens, and the glass is perfect, he "might" try the self-cleaning. Spraying a non-residue contact cleaner inside the shutter will do no harm on a Copal shutter. Just remove the glass first. And, of course this is not a Nikon 450M lens issue at all, as he said the glass was perfect, rather it is a copal shutter issue. Thousands of lenses uses Copal 3 shutters, all manufacturers.

AnzaRunner
14-Apr-2009, 15:59
It takes a professional repair person to do a proper CLA. Perhaps the seller would entertain the idea of paying all, or part of the cost of the service.

I checked the Copal 3 shutter on my 450M. I could repeat the problem that the OP described if I purposely did not cock the shutter all the way. However, a smooth continuous movement of the cocking lever seemed to engage a part that held the lever in the cocked position until the shutter was fired. If that part is worn, or broken, it might need to be replaced, adding to the cost of the repair.


The lens has hardly been used, so I don't think anything is worn on the inside. However, your statement that you were able to get yours to do the same thing makes me wonder if it is somewhat normal. If I cock the shutter like normal all is fine. I just haven't had any lenses in the past where you cock it to the point where it clicks, but it will pop open the shutter if you don't cock it absolutely all the way so it holds it.

I won't have any problems returning the lens, and with the number of 450mm's out there, I think I could pick up another one that is nice and clean. I just want to make sure this is not normal behavior.

Jon Shiu
14-Apr-2009, 16:11
I just checked my Copal 3 and it behaves the same way, so I don't think it is anything to worry about.

Jon

AnzaRunner
14-Apr-2009, 16:19
I just checked my Copal 3 and it behaves the same way, so I don't think it is anything to worry about.

Jon

thanks, you guys are confirming my suspicion that this is normal behavior. The lens is pretty much immaculate, so I have zero complaints if this is normal.

http://www.benhorne.com/photos/450lens.jpg

Gem Singer
14-Apr-2009, 16:29
Just make sure the shutter is fully cocked so that it doesn't spring open after you pull the dark slide, and you should have no problem.

I have found that if there are no broken or worn parts, simply exercising the shutter a few times will put it back into working condition. Loosens up the dried out lube.

From the picture of the shutter, it looks to be too new to have worn parts.

Use it in the best of health. It's a super lens for 8X10.

Kevin M Bourque
15-Apr-2009, 11:58
Hope it works out with your lens. I used one on 4x5 and it was just wicked sharp.