tommyinca

<p>The 'asterisks' are not your typical asterisks. They have triangular tips designed to measure minimum line width that the sensor can detected at that region of the sensor.<br /> <br /> The black quadrangles are designed to measure the white to black transition. They are slightly off-set to detect grey transition difference or other sensor artifice (ie: from color Baylor filter).<br /> <br /> The tiny dots are designed to test how the sensor can capture small details such as texture.<br /> <br /> BTW: This test pattern is designed such that it is easy for an machine to read and grade.</p>

<p>Could be a Kodak 616 half frame. Image size = 2 1/2 " by 2 1/8"</p>

<p>Canon made a gadget called Canon Auto Macro Ring. It will allow you you to control aperture using cable release and aperture ring (for when the lens is reversed)</p>

<p>Mount a M42 to K-mount adapter to the front of the bellow, then you don't have a K-mount bellow any more. Then look for a M42 or M39 RMS adapter. </p>

<p>One way using your bellow to get to > to 1:1 to about 3:1</p>

<p>- Use a M42 to EOS adapter to attach the Pentax bellow to the 5D<br>

- (Optional) If you want to use your double release, you will need to get a old canon mechanical to electrical cable release adapter (T3 adapter). Also get a cheap 5D remote release from ebay. Ohm out and Spice the two cable together. <br>

- Get a reverse lens adapter for the lens mount that you want for the reverse lens. </p>

 

<p>Stay away (Vivitar 28-70) unless you plan to use this lens for f5.6 or above.</p>

<blockquote>

<p>"Now that D800 has such impressive video function, I want to give it a try!"</p>

</blockquote>

<p>IMHO/FWIW, D800's impressive-ness is the sensor size and the large and cost effective fast lens system it has. If you keep it to f8 and f11 and can't manual focus, it will be like having a stick shift Lamborghi but drive it with-in the city limit of hilly San Francisco. aka: All show :-)</p>

<p>FWIW, Real Cinematography manual focus :-) And it is OK to mark focus points with tapes before hand.</p>

<p>Kodak fix focus Instamatic 404 has f8 lens. Work then should work now. But then why buy a D800.</p>

<p>Nikon bodies show effective aperture which include the effect of focal length extension when the lens is focus to close distant. Other brands such as Canon, Penatx, Sony/Minolta do not. IMHO, some good and some bad. It is something you just have to get use to like any other brand difference (lens mount on/off. focus directions and etc.) </p>

<p>PK lens are picky on EOS bodies. The ring has to be thin to ensure infinity focus. It is also hard to make it tightly fit at the same time. The seller will have less returns if it is a little loose than not have infinity.</p>

<p>K-mount lens inner aperture level are long. Unless you remove them in advance, the lens won't fit full frame body and in some cases certain lens-cropped body combo.</p>

<p>Taking the adapter ring in and out is more painful than say, a Nikon-EOS ring.</p>

<p>BTW/IMHO: I would still put up with above when it come to their 85/1.8, 28/3.5 K and their 200 macro (this one definitely if one can find one :-). </p>

<p>2X the price is never 2X the performance. IMHO, you may find 1/2 the price of a Nikkor in a Tamron 90mm macro not that much worst. Or for that matter, 1/2 again the price for a 100mm Cosina is not that bad compare to a Tamron. FWIW, Enjoy, after all you saved the cash for it :-)</p>

<p>Check out this 1911 $65 Kodak 5 by 4 folding camera Ad. Eyeballing, it is about a 160/6.3 lens (three elements?).</p>

<p>http://www.amazon.com/1911-Eastman-Zeiss-Kodak-Anastigmat-Special/dp/B005DGX8GO</p>

 

<p>Try format the card with the computer (assuming you empty out the old pictures first) using the card reader and take picture with the computer formatted card.</p>

<p>No such adapter existed at this moment. There are flange to sensor, rear diameter and other electrical/mechanical issues.<br>

Some common lens that can be adapted to EOS are M42, Nikkor, Contax, Olympus and Adaptall version of Tamron lens but not this one.</p>

 

<p>Assuming you are using an EF50/1.8, you will need about 48mm of extension tubes (Kenko 36mm+12mm) to get to 1:1 and has about 65mm of working distant (subject to tip of lens). However, it it another matter of getting 55+ lp/mm (about 300 DPI at full 18x12 print) of resolution at the edges with this set-up (you won't).</p>

<p>Do consider the weight and size of adding a 80-200/2.8 to your bag. </p>

 

<p>Sounds like dried up helicord lubricant. If you can't return it and want to risk, sometime warming it up with a hair dryer while turning will smooth it up. Note: Don't over do it, the same lubricant can escape and move to the aperture iris. You will then have a different problem to deal with. Do it at your own risk. </p>

<p>I say, a perfect 2nd Camera for a K-5 or K-r. They got it right this time. Take care of current loyal customers first. They learned from K10D.</p>

<p>IMHO or two cents worth, there are no perfect camera. There are many trade off an that is why there are many brands to choose from. It is a lot less stressful if you don't let the sale person talk you into buying one big expensive system. Instead, buy the minimal to get start (ie: one lens and one body) and nothing else (aka: skip the extra battery or filters). Use it for a while, if you don't like it, you can always un-load it in the used market. If you don't overbuy, this path is not that expensive. </p>

<p>FWIW, It all depends on how much control you have over the distant between the point light source and sensor. If none like in astrophotography, the longer the telescope (focal length), the larger the mirror/front element, the better.</p>

<p>IMHO, Reversing the lens may just effect the effective focal length and reverse the exit and entry pupil ie: sizes. May need some optical design instead of trial and error. </p>

<p>Here is a link to some disassembleb 55/2.8 micro nikkor pictures. May be it will give you some ideas. Sorry, not f3.5.</p>

<p>http://mm.ils.uec.ac.jp/camera/2005/micro.html</p>

<p>P.S. Don't forget to mark the helicord before you separate it from the focus bellow. If you did, it may take may days of trial and error to put it back together.</p>

<p>See if you can fix the filter ring dent first. You will need it if you want > 1X macro (reversing the lens). IMHO, fixing the focus ring is 10X harder. You almost have to take the whole lens apart and deal with repacking the helicord with grease. Lets hope you didn't pay too much for it.</p>

<p>I think focus breathing is a term used in the video/cinema-tography side. It may sound cool but it is a description of a bad lens characteristics, having a non-linear framing rate of changes, as one track a moving subject. BTW: It happens in more and more newer prime lens design too, not just zoom lens.</p>

<p> </p>

<p>Not C-mount security lens but Canon EOS is easy to adapt a number of lens from the 40s, 50s, 60s, 70s, 80s, 90s and so on.</p>

<p>For examples, Old M42 lens, Nikon Nikkor, Olympus OM, Zeiss Contax, Leica SLR, Pentax K-mount (some restrictions), T-mount/Adaptall and also others . </p>

<p>Looks clean-able. May as well clean the other clung on the side too.</p>

<p>It is a ~ +6 diopter with 49mm tread.</p>

<p>An easier to find close alternative is the matching closing-up lens used for the Vivita 100mm f3.5 macro. With that, you get about 1.7X instead of 2X. Result is not bad and some what close to the original with a D300S.</p>

<p> </p>