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I never consciously noticed such a sound, although it could be that you hear the mirror flipping back. The higher frame rates of the F70 and F80 make that these have mirrors that really 'snap' back while the F75 is decidedly slower and seems to 'slide'..

This isn't tied to manual focus or auto focus, it's got to do with how you configured the AE Lock button on the back.

 

What you need to do is go to the custom setting menu (the pencil symbol in the menu), and set custom function CSM 14, AE/AF-Lock to one of AE/AF-Lock ; AE Lock only ; AF Lock only ; AE Lock hold ; FV Lock

 

In other words, to anything other than 'AF-On'

 

If you have trouble setting custom function 14, then you need to make sure that in the basic camera settings (the wrench symbol in the mnenu), the option CSM/Setup Menu is set to detailed..

The F55 indeed doesn't support AFS and VR, and isn't fully connected, while the F65 is. But so is the F90, which I believe does work with AFS lenses, yet not with VR...

Hi Darren,

 

nice find on the patent! This explains a lot, and also tells about some stuff to expect in the future..

 

The R/W signals determine which way the communication between lens and body go.. The H/S(B) is from body to lens, initiating data transfer, the H/S(L) is from lens to body, enabling transfer. The command 34H needs to be sent to the lens to activate the VR feature according to fig.12.. So, you'd have to send a low pulse to the lens, wait for the signal low back from the lens, clock clk and simultaneously send 34hex on the si/o pin.

 

Something that's mentioned, but not present in any lens I know of is power zoom. This should get the rumour mill started..

The F55 (no AF-S, no VR) repair manual page 75 shows the following 7 connections to the lens:

 

VCC, R/W1, SCK, SI/O, R/W2 (Unconnected), ? (Unconnected), GND

 

called respectively VCC, LENSB, LENSC, LENSD, nothing, nothing, DGND on the flex cable..

 

From this one can imagine that the '?' pin on the F65 and upwards serves as battery power to power the motors and actuators in AFS and VR lenses..

 

I've found some on the accelerometers on the VR lenses:

http://www.nikon.co.jp/main/eng/portfolio/about/technology/nikon_technology/vr_e/index.htm

 

Apparently VR operates in different ways depending on whether the shutter button is pressed halfway (smooth), just before exposure (center) or during exposure (correct all).. So, it's not just a simple matter of on/off that the camera sends to the VR..

The lens tells at least

 

- focal length, but probably also the range for everything ranging from programmed exposure to speedlight zoom settings

 

- distance (AF-D/AF-G)

 

- aperture range, to allow P and S mode to work

 

- aperture correction, to display correct A on variable aperture zooms and macro lenses

 

- supported functions such as AF or AF-S to tell the camera whether or not to drive any of these, or whether they're disengaged on the lens (can't have shutter lock in manual focus mode)..

 

Both from the manual and from peeking inside my camera, there seem to be 7 connections, not 8. And I couldn't make out whether those quoted were correct. But the most probable meaning of the mentioned connections is as follows:

 

VCC = supply voltage for integrated circuits (regulated voltage)

 

DGND = ground voltage for integrated circuits

 

LBAT = battery power for driving motors/actuators (unregulated

voltage)

 

LGND = battery power ground voltage

 

SIO = serial input/output for data/control, bidirectional

 

SCK = serial clock for timing SIO signals

 

R/W = don't know. Could be anything e.g. read/write to control the direction of SIO

The "5 AF point" rule indicates the age of the camera. It's just a coincidence that Nikon was able to find a dividing line like that.

 

If only things were that simple, the F55/N55 is decidedly more recent than the F80 and F65 cameras. It's limited to 3 AF sensors, and doesn't do VR...

It's not likely that a simple on/off signal suffices. The VR funtion is only available on Nikons with at least 5 focus points. Makes a lot of sense, as the AF sensors are presumably used to measure the amount of movement in the vertical and horizontal direction (with complementary sensitive sensors). Given the limited number of contacts, the corrective signals are probably coded and multiplexed,

just like those for aperture, focal length, distance, AF-S and whatnot are..

One of the options not mentioned, but possibly worth considering is the SQB. They have similar specs to the SQA. The SQB has mirror lockup, and also has a 1/500 when the batteries run flat.

 

Depending on what you want from the camera, there are three things missing compared to the SQA-i; one is the contacts for a metering prism, second is a built-in flash meter, and the last is a 'B'/bulb setting for the shutter. You're relegated to the 'T' setting on the lenses, and exposure is all manual..

 

The good point is that the SQB's come a lot cheaper than the SQAi and as they were introduced in '96, they're all quite recent.

Get an MB-18 battery pack for the F75. The MB-18 takes four AA batteries and has a vertical shutter release button. That's something even the N80/MB-16 combination doesn't offer.

Nikon did indeed produce full frame DSLRs in the past. They didn't achieve this with a FF sensor, but through additional glass inside the body of the <A HREF="http://apphotnum.free.fr/N2BE2.html#E2">E2 and E3</A><P>

 

Whether they'll ever go FF again in the future remains to be seen. In the end, digital has liberated the manufacturers from a standardized (36x24) image format. But even if Nikon never goes FF again, there's some logic to using FF lenses, even if only to be able to use film bodies as indicated above. On DX bodies you'll use the sweet spot of the lens, you'll have less vignetting, and some focal length ranges are just not available in DX format. Besides, some of the older lenses have a fit and finish that you don't get new for the same money..<P>

 

However, if indeed Nikon decides to go affordable full-frame sometime in the future, that doesn't mean that you can use the FF film oriented lenses just like that. The FF sensor may require specifically designed lenses to get best results..<P>

 

So, I'd buy lenses that go well with the D50 now, whether FF or DX, and not anticipate on what will or won't be available 5 years down the line..

Being stuck at 1/60 would be odd indeed, but there are some things that may cause underexposure..

 

The shutter speed is limited to 100/ISO, which for 1600 would be 1/15. If your aperture isn't large enough, 1/15 may just not be long enough to avoid underexposure.

 

Another point to consider is the button inside the flash mount. If it's pushed in or stuck, the shutter speed is fixed to the flash speed. Depending on model it's somewhere in the region of 1/125. Don't know if the 2x button makes it a fixed 1/60, but it's worth checking out.

 

Hope this helps..

Hmm, I'll try that again..<div></div>

Rusty..<div></div>

Neither the dynamic nor the closest subject mode was selected.. plain 'single area'. It isn't the hunting for focus that distracts most, it's the seizing up thing. Not only the 90 (tamron af sp 90 di) was at fault, the 50/1.8 did it too.. and that's supposed to be an ok lens as far as AF is concerned, isn't it?

 

By the way Jerry, nice photo!

Just had a days worth of shooting a company outing with the D50 plus 50/1.8AFD

in overcast weather. Light was generally reasonable (1/125 at F8 for ISO200) if

a little flat and hazy. And although I got a bucketfull of good shots, I also

experienced AF problems galore. It appears the D50 hunts more than the F80 and

F75 despite having the same cam900. What's worse is that every time the AF

can't lock on to something, it zips to the closest focus distance and remains

there locked. Activating the AF again and again doesn't work unless you poke it

something contrasty in the face to unseize it. The F80 and F75 would always

cycle if they couldn't lock and hit the closest focus.

 

I've tried out different lenses, and found that a slow 3.5-5.6 zoom gives no

trouble (go figure!). It's worst with a 90mm macro set to full range. It's

almost like the D50 wants to focus on the ground glass itself for lack of

something better..

 

Anyone else noticed? Or know the best settings to prevent this? I've got AF-S,

the rear button set to simultaneous lock AF and AE, and the center cross sensor

selected..

Mine's an SQ-B, but that's exactly the sound the mirror and the baffle make when I advance to the next frame. It's been like that since I bought it new, so I suppose it's meant to be that way; a hollow metallic 'clonk-clonk' (for lack of a better onomatopea).

 

I'd only worry if there's something obviously rattling from being loose.

Even if the F75 is working properly, it doesn't hurt to clean the DX contacts inside the camera once in a while. When dust has settled on the contacts, an erroneous DX reading sometimes occurs. Use a tissue and gently wipe the contacts clean.

<div></div>

Though Martin's answer makes a lot of sense, it still doesn't touch upon something really odd..

 

The 'more than 5ft' doesn't state at which aperture (f4-f22) this is.

 

If you play around with a depth of field calculator, you'll find that it just doesn't work around f4, which is the largest aperture available on the AL. The point of focus would have to be at 6ft, but the far point of sharpness would be about 8ft. Hardly infinity.

 

At f22, the smallest aperture, if the point of focus is 6ft, DOF would cover 3ft to infinity.

 

Neither situation matches the 5ft-infinity claim..

 

Why not take a picture at the largest aperture (f4) and have it enlarged to the point where you can make out where the camera is focused?

Don't forget that DOF isn't only usefull at f32 or so. I find it also very helpful in the f2-f8 range, where you have to judge whether the background is blurred enough..

" One of the things about a camera that you never have to turn on its side is that they are less demanding when it comes to tripod heads. "

 

No, but if you want to point down or up instead of level, the ball head still needs to cope with the considerable weight of the Bronica.

My personal preference is JPEG-FINE.

 

This means that when I run into a printing station somewhere, I can insert the memory card, and have prints immediately. Not every place has the software installed to handle the D50's NEF..

Ginon,

 

I just clicked a bit around and from your posting history, I've seen that you've had earlier underexposure problems with the GT. You've shown some indoor pictures to illustrate that. What I've noticed, is that they have fairly extended depth of field, i.e., that they've been taken at small apertures like f16 or so. You didn't forget to open the aperture up to the f5.6-f2.8 range when you were inside, did you?

 

There's a slider in front of the meter cell that lets more or less light through, depending on the aperture. The amount of light that falls on the meter is independent of the ISO set. When indoors and at f16, not enough light registers in the meter cell, the meter hits the slow speed limit and you get underexposed pictures. Faster film doesn't help to make the meter more sensitive to too little light hitting the meter.

 

When indoors, open the aperture so that the shutter speed needle goes to 1/30 instead of staying in the low shutter speed range. It helps to have 400ISO film to get to 1/30 indoors of course, but you really need to have the aperture opened up to f5.6-f2.8 ..

Go outside on a sunny day without clouds. Set the aperture to F16 (hence sunny-16). Point the camera at something middle grey. Look at the shutter speed indicated by the needle. This should approximately be 1 divided by the ISO value that you set on the bottom of the camera.

 

For instance, with the ISO dial set to 125 ISO, the needle should go to 1/125 when the aperture is at f16. With the ISO set to 400, the needle should be just under 1/500 under the same conditions (F16 aperture, sunny weather, middle grey subject).