nmcmahon

<p>Thanks for the solid response Edward</p>

<p>Sorry, maybe i'm not clear, I want to use an underwater finder above water. will a 15mm underwater finder be a 15mm above water finder?</p>

<p>I'm looking for a 15 or 18mm finder for a handheld large format setup I have with a 65mm lens. I seem to come across many underwater finders for a reasonable price and am attracted by their large size. <br /> But<br /> Is the coverage of a ikelite 15mm finder the same as a standard above water 15mm finder ( I believe you lose about 25% coverage underwater) and is their a focusing difference.<br /> Basically if I use a 15mm underwater finder above water will it have 15mm coverage and will the image be in focus (or is this irrelevant)</p>

<p>I'm looking for a 15 or 18mm finder for a handheld large format setup I have with a 65mm lens. I seem to come across many underwater finders for a reasonable price and am attracted by their large size. <br>

But<br>

Is the coverage of a ikelite 15mm finder the same as a standard above water 15mm finder ( I believe you lose about 25% coverage underwater) and is their a focusing difference.<br>

Basically if I use a 15mm underwater finder above water will it have 15mm coverage and will the image be in focus (or is this irrelevant)</p>

 

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<p>ay on a bright cloudless day where there is no pollution in the air after rain or high winds as I get here in beijing everyday</p>

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<p>Sorry not everyday but once a month at least!</p>

<p>Sure daylight can vary wildly but my meter is wildly out. Say on a bright cloudless day where there is no pollution in the air after rain or high winds as I get here in beijing everyday when the sun is at its highest I should expect to get a fairly accurate guestimate at the temp and fairly sure the cc should be spot on. Or does anyone have a better idea for a known accurate colour temp source?</p>

<p>

 

<p>It seems that no-one calibrates these meters anymore.<br>

Has anyone attempted to calibrate themselves? I've investigated my minolta 2 color meter and noticed one adjustment screw behind the lb/cc index chart on the back of the main body and six adjustment screws once the rear of the sensor housing has been removed.<br>

If anyone knows or has carried out services on these meters it would be a great help to know which screws do what. I presume that the six adjustment screws behind the sensor adjust high/med/low levels for lb and cc each they are in sets of three. I tried adjusting the lone screw behind the body but this made no difference to my readings. </p>

<p>My presumed method would be to set up a light source of known colour temp (daylight) then filter out using filters over the sensor for highs and lows and adjust untill I get accurate results. Considering a new meter is in the region of $1000 I'm willing to take a risk on something that is worth little to me now. </p>

 

</p>

<p>Anyone attempted to calibrate themselves? I've investigated my minolta 2 color meter and noticed one adjustment screw behind the lb index chart on the back of the main body and six adjustment screws once the rear of the sensor housing has been removed.<br>

If anyone knows or has carried out services on thiese meters it would be a great help to know which screws do what. I presume that the six adjustment screws behind the sensor adjust high/med/low levels for lb and cc each they are in sets of three. I tried adjusting the lone screww behind the body but this made no difference. <br>

I set up a light source of known colour temp (daylight) then filter out using filters for highs and lows and adjust untill I get accurate results. Considering a new meter is in the region of $1000 I'm willing to take a risk on something that is worth little to me now. </p>

<p>Reasons, its in the title. instant + film. <br>

when i've used digitals for proofing, results have not always been accurate and iso's were not what was stated in camera, but i don't use instant film either. I test my equipment and use a spot meter.<br>

Not everything is a pro and con decision.</p>

<p>There are three luns pro sbc's going on the bay uk at the moment. very reasonable</p>

<p>Got the slide back and the ballance was correct for blue with the 80a and c together with suggests that the original reading was correct and reading through filter does not work. But the magenta cast on the neg was large, originally the there was very little green correction advised but after reading through filters about double the amount was stated, i've taken into account reciprocity etc. Has anyone have any comments on their experiences with this kind of thing?</p>

<p>I just sold my Grandagon 90mm 6.8 two days ago. I seperated it from the shutter and did not notice any spacer involved. I'm about 95% sure, but may be better taking someones advice who has one is his hands.</p>

<p>I almost addressed the question to you Ellis, thanks for the reply.<br>

I'm not so worried about the high red reading, its a 60/40w bulb and the ceiling is a reddish ply so I would expect it to be such. <br>

I thought that if a get a reading recomending a 80a filter, measuring through a 80a filter would give me a recomendation of no filter (ie 5500k). I assumed this would be a full proof test of the meter and filter. I'm using lee resin filters so would presume they are accurate.<br>

For example I have taken a measurement recomending -238 I put a 82c filter over the meter and get a reading of -206, meaning that the filter is providing -32 of filtration, but the 82c on the back of the meter is quoted as providing -45. (possibly the meter tops out at these high warm temps? giving readings lower than their true value)<br>

This is the first time I've used temperature filtration so I may have misunderstood the principles involved.<br>

The light is not some spikey source but a tungsten bulb so I would presume readings and filtration would provide pretty predictable results, maybe my meter is seriously flawed. The readings I get though are repeatable and stable.</p>

<p>If just got a set of lb/cc filters and a minolta meter II. I'm getting readings of -250 blue required for daylight film under a tungsten bulb attached to a reddish wood ceiling. The value may well be this, but I have a 80a and 80c filter which combined should give me something close. As my meter does not give the value of correction for a 80a filter I measured the light with the filters in place and got a value of around -80 req. I then measured each filter individually by measuring the source with and without the filter over the meter and the results were not what I expected. I.e when I re measured the light with the recomended filters over the meter I was not getting daylight balanced readings but readings that still required further filtration.<br>

Am I missing something?</p>

<p>If you can't find another consider the Gossen luna pro SBC. I bought one for night time work for around $70 in mint condition. Realisticly the sbc measures down to -8ev. The dial centers 0 on -5ev but the needle can still display another 3 stops below that! I'm doing it now as I scan my studio. The are quite common too .</p>

<p>1. Buy both and try them each for a couple of days.<br>

2. Choose one system and then send me the other.</p>

<p>I guess i'm an expert on this so......<br>

I used to use a lab in sanlitun south street, a fuji branded lab... untill recently that is. The negs looked fine but when it can to scanning they were incredibly dirty. Either their washing was not adequate enough or they were filing the negs when they were still slightly damp. <br>

The no. place is probably Today photo which is located near beijing west railway station (come out of the entrance and take the road leading north and away from the station to the left of the station and its about 50m on your right is a glass building. very professional and something around 20 rmb per roll.<br>

next is near meishuguan the nation chinese art museum at the north end of wangfujing the main shopping street. its a kodak shop and is located in the side road that is opposite the east exit from the museum and about 20m north of it. again around 20rmb but no contact sheet included but can do 6hr processing.<br>

The other place which I have just started using but have heard great things about is a shop located in the west of Beijing, but which have a collection every day at 10am from the photography studios of the central academy of fine arts (CAFA) locaed in wang jing near dashanzi 798. They charge 5rmb for reel proccesing and 12rmb for dip and dunk. I collect my first negs there on friday. but they have a 24hr turn around if no contact sheet is required.<br>

Depends on where you are located as Beijing is all about the traffic and time costs.<br>

my website is here <a href="http://www.nathanielmcmahon.com">www.nathanielmcmahon.com</a> here you can find my email and telephone number, feel free to call I would be glad to help as the instructions may not be that clear.</p>

<p>I would seccond the suggestion that you start out on a static subject. I started with a sinar a year ago and one of the first subject was a model. It was hell! getting her to stay still while I focus adjust etc load. The shots were'nt very good and disheartened me a little, forget flash for now. the shot were a little overexposed the image circle had not covered the whole film due to shifts I made to speed things up. Use a subject in which you can take your times studying what you are doing. Follow a step by step procedure and memorise and stick to it. I fyou are using black and white read up on the zone system, its actually increadably easy (with a spot meter).</p>

A quick scan on ebay will tell you that for $3000-$4000 you may be lucky and get yourself an 11-12mp back but probably not a 16mp. I make a living form art repro, so have a bit of experience. Film is the way to go unless you can afford a modern digital back. Where are you based, can you use a film mailer? For example a mamiya rb with a 127mm or 180mm lens, fuji astia and a decent scan will do as good as you need probably. and will cost you around 400 euros. But if you have a hard time sourcing a place to develop you will have a much harder time finding a place to do a drum scan.

Do you have strobes, a decent tripod? if not then for your budget a very decent film camera and mid level strobes or a DLSR setup that will give poor results. If you already have the camera, lens, lights etc and capability to fit a digital back to it then maybe you can find something for your budget.

Problem with digital slr for art repro is tone. You just can't capture the high and low levels like film can on medium format. You will have poor blocky separation in the high and low tones that will make some paintings look like they were by numbers. Not sure about what a modern 5ds II and decent prime lens can do though, but would be surprised if it came close to the subtleties of tone that a medium format outfit could.

Where are you based?

"The springy feel the unlocked revolving back is normal. It only has to be tight when locked."

 

This is the problem, it is not tight when locked. With the rev.back on the body there is an extra 2mm i can push the rev.back to the body using a little push. It can't be the stricking pin as nothing is there for it to push against, i realise now. Maybe the seals but I can't imagine they have any affect or provide enough pressure to push it out by 2mm.

 

Anyhow thanks for the help, It needs someone to take a close look I think.

anonther thing i've noticed is that when the shutter is depressed but not fully depressed. the right hand side pin comes out of the rev.back by the same amount you depress the shutter release. The left hand only quickly shoots in and out upon actual firing. This leads me to think that the right hand side pin mechanism is set forward too far or is too highly or weakly sprung.

Thanks for your detailed response,

It's easy to get carried away and misinterpertet peoples genuine aid, sorry.

I'm living in China at the moment, so I guess a visit would be out of the question. I would love to have it overhauled but no-one here is trained or really cares as they are very cheap to buy used.

From following your instructions I think I have noticed what is causing the problem. with the rb lens down on the table and the rev.back postioned on the body (not locked) all corners are flush with the body bar one the upper right. There is a certain mechanical springyness to it. The seals are in very good conition and seem to be a perfect factory one peice fit. In pushing the non flush corner to the body it emits a sringy squek. The two peices of metal that stike the rev.back when the rb is fired (mechanism that hits the back to register an exposure); the right hand side one does not depress as easily as the left hand side one and is exerting some force which is pushing the back out of line. (Sorry I hope this is clear, I can postpics at thge moment) I have no idea about the mechanics of this mechanism as I never opened the body up.

I'm 99% sure that this is the problem, the same force required to make the back flush is the same required to push this pin/edge back. Looks a little more complicated than I had first thought. Hope this sounds familiar to you.

I use a heidelberg s-3900 with very old software that does give any prescan or visual interpretation of the scan,

only lets me scan is 8-bit and has not feature for loading color profiles.

 

Does anyone know of any other software available for this machine?

 

My eyes lit up when I saw a heidelberg supporting silverfast ai but for some reason it does not support the 3900

only the 3400.

As I have said before, Every rb I have looked at has this problem to some degree (thats around 10-15 I looked at when I bought mine second hand last year), in my case it sits about 1.5mm away from flush with the body. It's not the seals they are fine.

Yes of coarse if you pull it will come apart, I am not a baboon and I neither consider this normal usage but was mearly suggesting the action as an illustration to highlight my problem.

Admitedly my rb does not always sit in a comfy warm studio but follows me through all sort of terrains. I do not abuse it, but the camera back does not like being packed into bags and lugged around. This camera can take a lot of punishment but in this environment the one thing that is not up to the rest of the cameras build is the back.

I cannot overstate the fact that every camera I have looked at has this problem to a degree and it may not even be considered a problem to most.

If you have never encountered this problem then please refrain from telling me how to use my camera, I cannot treat it with any more care. Rb's have been given a new lease of life and are being used in situations they were never designed for i.e. the studio environment. I'm not complaining

I am not attacking the camera but merely suggesting an improvement or adjustment to keep this beast prowling.

In my opinion the metal strips securing the rev.adapt. could be stronger, has anyone done this?

If you imagine pulling on the back of your rb film holder and the revolving adapter moving a couple of mm from the body noticably in the top right hand corner. you don't actually have to pull mine is not held tight to the body. I have taken apart the lock mechanism and looked at the metal strip that secures it to the pins and they are bent because the long thin peice of metal is flimsy and not strong. I know no way of tightening or adjusting the rev.adapt to the back. Having looked at the camera market at the piles of rb's they have for sale all of them have this problem to some degree, you can always push the back closer to the body. The rb is a great tough camera, its only weak points lie in it's back construction quality, in my opinion. Anyone else found this problem