Jay M

Acquired this Sun wide zoom lens (24-40mm f/3.5) couple years ago and tried out on a digital camera (D800) with really nice results so decided to use it with film, the Ektachrome, see how its going to look like.

As matter of fact there is indeed another a good option from Pocket Wizard but an oldie item for sure, which can be used with pocket wizard plus ii or equivalent radio slave transceiver for remote control.

No easy solutions with only one rare option but expensive and hard to find these days, the Nikon MW-2 radio control set, see the screenshot from F4/F4s/e manual below and you may search online to learn more about it. Good luck.

Well, sounds like an AF system issue to me which's not straight forward for troubleshoot while kind of not expected 'cause I have never experienced such an issue myself with quite a few F4 variances in hands over years but it could fail based on a N2020 that I acquired cheap has failed exactly like what you described with an intermittent AF and finally dead out (tried few things myself to save it but no luck) leads to the nice look camera totally useless even manual focusing won't fire although meter still works like a charm, then keep it as parts for myself without bothering to fix or sell, so the F4 from similar or little later era of old AF technology may fail like that probably (sorry to say without absolute certain) and hope you can find a solution to it.

Try to determine which part is failing by doing this quick - remove DP-20 viewfinder then turn camera on and off, AF/MF focus as usual, of course you cannot see through VF but should be able to tell via the small focusing-aid LEDs on top front of camera body if lit or not right, etc., if works repeatedly without VF, then DP-20 may or may not be the issue due to the cracked small LCD screen in the viewfinder (not sure how but might be from an impact damage before?) or simply the contact pins loose seating connection (hopefully the latter) then you should know what to do next. Good luck.

LA, California, IR converted D100 with 18-55 DX VRII.

First of all I verified with my F4 and SB-24 that dry-fire of camera with flash hotshot mounted should work without issues regardless of M or A mode or frame counter being set and even higher shutter speed than 250 in manual mode would still fire. Then I'd suggest to remove the DP-20 viewfinder from camera to inspect the contact pins (refer to the diagram below) especially a and b are clean and moving properly with a multimeter if possible to check connections, try again. If DP-20 and F4 seem good to you, likely the culprit is the flash (test fire or another good flash to verify). Also, check the ISO setting dial that should not be in DX mode by accident which will cause flash out of order in "Err" mode as shown on flash panel. Hope this helps.

Note, robbing to clean the sticky area gently to NOT to remove the adhesive but making it stickier.

Since there's this photo try this first, while assuming the sticky surface on the strip end still remains, use a cotton q-tip dipped with robbing alcohol to rob/clean both sticky strip and groove areas a few times and let it try out a bit then reattach it back to the groove firmly, hope it works without the double-sided tape fix as suggested, good luck.

Found this old stack online couple years ago with a fraction of the tag price and didn't know such an interesting product ever existed ...

I'm not familiar with this AF-S(?) 105 2.8 lens in particular but based on the AF/M switch mentioned without research I'd assume it's a AF-S lens, correct? However, I did have the same experience with the 28-70 2.8 AF-S lens myself years ago, e.g. lens stops AF function as soon as it reaches 10ish ft-mark towards to infinite and causes camera body hang/freeze at same time then had to switch to manual and restart camera to continue, VERY annoyance. Tried to "fix" it myself in risk and couldn't find anything wrong by naked eyes inside of lens assembly. After all decided to depart it in a condition of as-is for parts or repair, never looked back. Sooner or later, learned from online that there tends to be some AF or electronic issues with old AF-S lenses (not confirmed) but just my own stories for your references, and good luck.

Downtown LA Nikon D800 20mm 2.8 Ai-S

+1

Ever considered to convert your old DSLR for IR ... here's one done myself last year to my D100 and enjoyed it every single time when I had a trip since then ... it's alive again.

Not often seeing color film in medium format and Agfa Optima 100, here's one, with Bronica SQ-A and 80mm 2.8 lens in 6x4.5 format