Camera

Advise please!! Which specifications do I need to get camera lenses that can capture details of the iris?

admin — Sat, 19 May 2012 04:43:38 +0000

I want to buy a Nikon Digital Camera, and then fix a special type of lenses that can capture details of the iris. Which specifications do I need to mention? Is there anyone who specialized in Nikon cameras?

Any 100 year old camera can do that if the lens can focus closely enough.
Old triple extension bellows cameras were OK, with a shorter than normal focus lens attached to get very close focusing at large image scales.
This is a Thornton-Pickard, the Rolls Royce of triple extension cameras
http://randcollins.files.wordpress.com/2010/08/thornton-pickard-royal-ruby-triple-extension-camera-with-roller-blind-shutter.jpg

Remember physics at school?…the basic lens equation.
1/f = 1/v + 1/u
Change the object distance and you change the image distance
Magnification = image distance/object distance
M = v/u
At 1:1 image scale, the image to object distance is 4F.
That’s the film plane to the eyeball you want a picture of for example.
That 4F is 4x the focal length of the lens so to get 200mm working distance use a 50mm lens and for 400mm working distance use a 100mm lens for a same-size image.
http://drt3d.blogspot.com/2008/02/basic-lens-equation.html

Tubes or a bellows unit let you change the image distance so can focus closer…
It’s been very common in hosptal practice for well over 70 years to photograph eye defects, lesions and wounds etc..
I used my lovely old Exactas for that kind of stuff, and for close-ups of skin lesions etc and microscope work.
They were made long before auto features appeared on cameras and had no light meters. A separate light meter was used.
http://www.thecamerasite.net/01_SLR_Cameras/Pages/exacta.htm

That formula works for far away things too, even how big the Sun is on a photograph or how big a barn is on the film from two miles away using a particular lens and there is a geometrical way to do it too, and a quick way of converting angular sizes to image sizes.
http://answers.yahoo.com/question/index?qid=20110622083741AA3GZAm

Here is a photograph of an eye, which is easily done with any 35mm film camera or a digital camera having close-up facilities as mentioned.
http://www.telegraph.co.uk/health/8782723/Trial-begins-into-stem-cell-treatment-for-sight-loss.html
More photos
http://thechive.com/2008/12/01/a-closer-look-at-the-iris-21-photos/

Close-up lenses
You can use them on any camera but SLRs are best because then you have a focusing screen on the camera..
http://www.alanwood.net/photography/close-up-lenses.html

Extension tubes. You can get them for all interchangable lens cameras.
My Exacta cameras have extension tubes more than fifty years old.
http://www.toledo-bend.us/index.asp?ExtTube

Bellows
http://www.alanwood.net/photography/bellows.html

For lighting you need a high speed flash, thyrister controlled, for speed and conveience or you’ll have long exposure times for large scale images.
You must set a very small aperture to get enough depth of field at large image scales so the shutter speed must be longer to compensate or the flash exposure must be higher.
1/20 000 of a second is fast enough for the flash to catch the iris before the iris closes in response to the flash.
Set manual flash on the camera and adjust the flash output if it has one.
At that speed reciprocity failure comes in so you can’t trust built in flash meters…
.No more link space left here (10 max allowed ).
Look up reciprocity failure for film and digital.
You can use tissues to cover the flash and reduce the output which will also soften the light for good results, and using the flash on a cable instead of on the camera lets you change the flash to subject distance for more control..
Some flashguns have full power, 1/2. 1/4/ 1/8 etc
http://www.amazon.com/Vivitar-285HV-Auto-Professional-Flash/dp/B00004TVSP/ref=dp_cp_ob_p_title_0

What are the names of these canon camera lenses?

admin — Thu, 17 May 2012 02:20:55 +0000

I need 2 Canon EOS Rebel T3i Digital SLR Camera lenses. One lens that makes the background blurry, and a fish eye lens that doesn’t have the black parts on the side while I’m filming. Also, I heard some canon cameras only take photos but do not film. I have not bought the camera yet so I want to know if this camera takes photos AND videos or just videos.

For the "background blurry" effect, this is more of an in-camera technique than any specific lens. The faster the lens (the larger the aperture) and more telephoto it is, the more background blur it will have – if setup in the camera properly. There are many lenses that will do this.

Any lens that is f/2.8 or faster, or a telephoto lens above 100mm will work for this purpose – again when used properly.

I created this photo with a 200mm telephoto at f/5.6, so all you need is either a fast lens OR a telephoto lens:

http://www.caribbean-cruising.net/ports/aruba18.jpg

Nikon though does have a DC lens that has a decoupling (or de-focusing) element that assists in blurry backgrounds (as well as blurry foregrounds), but I am not sure if there is a Canon lens with the same feature.

The fisheye lens you want is a "diagonal fisheye". Circular fisheyes and the cheap add-on front lens fisheye filters produce the circle (with the black parts) you don’t want. A diagonal fisheye does not.

Circular fisheye:

http://www.sigmaphoto.com/client/images/productphotos/08142009_img_97451.jpg

Diagonal fisheye:

http://www.sigmaphoto.com/client/images/productphotos/bondi1.jpg

What is the best SLR camera for a beginner?

admin — Wed, 09 May 2012 19:37:05 +0000

I am going to be taking a photography course in the next academic year, and for me to do this I need an SLR camera. I know a little bit about them, mainly from what friends are currently teaching me.

But I don’t really know which type to use for starting off so that I don’t get swamped or confused too soon in learning.

All help is appreciated.
Digital is preferred.
I already know that its a digital course.

But I will also in the future be doing film as well.

Before spending any money on a camera, email/talk to the teacher of the photography class you’ll be taking and find out if you’ll be shooting film or digital. The Rebel T3 and Nikon D3100 are two good entry-level DSLRs. If you’ll shooting film, ask the teacher what he/she recommends.

How to install security cameras and ethernet in new home?

admin — Sun, 18 Mar 2012 23:48:16 +0000

I am having a brand new house built, in the next couple of weeks it will be at the point where I need to install my own ethernet and security cameras before drywall goes up as the builders do not do this themselves. If anyone has any tips of how to online it will be much appreciated. I want ethernet in every room and 4 cameras out doors.

First off, plan. Walk the layout carefully and a paper map that you can mark up may be helpful as well. You can make a photocopy of a floor plan or hand draw this, it doesn’t need to be exact, but you need a really good idea of where you are putting things.
Before you do anything else plan where your router will go. This is the most important thing to plan for because once the dry wall is up you will not be able to change your mind on it. Make sure to plan for any kind of ISP you may choose to have in the future, so both cable and telephone will need to be wired into this room where the router will be. That way if you decide to change ISP’s they can install the modem in that same room. Trust me, nothing is worse than having your Ethernet wiring job perfect only to find out that it is then useless because you can’t put the modem in the room designed for the router.
Make sure when you layout where the cables will go that they will be protected. None should be exposed to extreme heat or cold and you especially want to make sure they will not be accessible to small animals that may get under the house or into the attic. Small critters love to chew cables, they will destroy your Ethernet very fast and all will be for naught.
Install your patch panel. All of your Ethernet cables will need to run to a patch panel if you want this to look clean. I do not recommend putting the panel built into the wall, instead plan to have it in a place where you can quickly remove it from the wall so you can re-punch any runs that need it in the future.
Run the cables. Run each cable then from the patch panel to their destination making sure to leave slack at both ends, usually between 6 to 9 inches of slack on each end is plenty to then work with it. Do not punch down anything yet. Make sure when running the cable that it is out of the way of where the drywall will be installed and that you do not kink or crimp anywhere, especially around corners. A rule of thumb is that the Ethernet cable should never bend more than if you were to wrap it around your hand. That is about the tightest corner you want to make it do safely.
Attach the Ethernet cable up and out of the way using a staple gun with special wiring staples (they are wider and rounded so they don’t kink the cable but you still need to be cautious when putting them in, don’t puncture the cable at all) or you can use some nails hammered in on each side of the cable and bent over to hold them in place. the second method is safer but more time consuming.
When planning and running the cables run at least 1 spare to each outlet. This will help you out later if you make a mistake or need to replace one cable. You may also want to run a fish line, no not fishing line, a fish line. It can really be just about any durable string you can use to pull a cable through the wall after the drywall is in place in case you need to replace one cable.
Make sure to mark each cable on both ends. Come up with a system that works for you, I usually just number them then mark those numbers on my map. Some people designate the room the cable goes to a letter and the outlet gets a number then the port on that outlet gets a number as well so those look like: A-3-1 (just an example). By marking them all on both ends you can trace each wire out when you are ready to punch them down and know which port goes where.
Once they are all run, you have slack, you are positive they are out of the way for the dry wall to go up, just wait for the house to be finished. When it is done punch down your cables at the patch panel, punch down your ports for each outlet (don’t put ports on the spare cables just leave them in the wall just for emergencies). Put your face plates up then you will need your modem plugged into your router, your router will need to plug into a switch (because you will probably need a lot more ports than a router will give you) then the switch will need to connect to your patch panel.
Once that is all connected and ready to go you will need to go around and test your ports. You may want an Ethernet tester for this to verify you have the correct pin out. I would recommend doing a search online for the pin out config.
For the security camera’s I would recommend using WiFi capable cameras for outside and Ethernet connected ones for inside. Or go WiFi with all of them. Just make sure you have an electrician install a weatherproof/tamper-proof power outlet near where you want them and you are good.

Reviews on Nikon L120 as a Bridge Camera?

admin — Mon, 27 Feb 2012 01:01:47 +0000

Is the Nikon L120 a bridge camera? I have heard good reviews about it, although some people are questioning that it is a bridge camera. Just wondering if anyone knows anything on the L120 and why it might not be a bridge camera. Much appreciated, thanks

The Nikon Coolpix L120 has a good zoom. It LOOKS like a real camera, but it is ridiculously basic. It has no view finder, no hot shoe (so you can never attach a decent flash) and NO manual modes (only the auto scene modes) !!!!
Without manual controls you are very VERY limited in what you can do, and very limited in how much you can learn from and grow with the camera. It also not possibly to attach a decent external flash, so all you’ll ever have is that very inadequate little thing on the camera.

If you’re happy to forever stay on Auto, take simple little snapshots and let the camera decide what to do, then you’ll probably be happy enough with it, especially if you intend to only take photos in excellent light conditions – they’ll turn out quite well then.

If you want to learn, improve and get creative, then this is not the right tool for you. You need something with more options and more controls.

Can you use Nikon lenses for film cameras on your digital camera?

admin — Mon, 13 Feb 2012 14:12:43 +0000

I was told that Nikon digital camera lenses are interchangeable with Nikon film camera lenses…the difference being that lenses made for the film cameras cost significantly less than those made for the digital cameras. Does anyone know if you this is true?

Yes…and no.
There’s a chart here to show what works….

http://www.nikonians.org/nikon/slr-lens.html

Best camera for taking Phone Reviews?

admin — Thu, 09 Feb 2012 03:54:12 +0000

I’m very new to Cameras , i have tried reviewing a phone using many cameras but the phone screen is blur while recording, can any one please suggest me a good camera for recording phone screen, with out blur.

Canon Vixia HF G10.

What is a good camera lens for night photography?

admin — Wed, 25 Jan 2012 10:57:07 +0000

One that can capture the moon, or the dark sky with clouds? The camera I have isn’t even close to taking a decent shot of the night today ): So what’s a lens that will provide me with a clean, crisp and colorful imagine of the night sky?

That depends on what camera you have.

Where can I buy used film camera lenses?

admin — Wed, 18 Jan 2012 05:14:31 +0000

I am looking for affordable lenses for my Sony F3 Camera. It has a PL Lens Mount. Does anyone know of a good source for lenses that can be used with this camera?

http://www.keh.com/

I have ordered several used lenses and camera bodies from KEH, and have never been disappointed. They also have a fair rating system and a good return policy.

which slr camera is the best for recording and photographing?

admin — Wed, 11 Jan 2012 06:10:38 +0000

which slr camera is the best for recording and photographing in the same time?can u tell me the medium price slr camera with the best quality?

It depends your budget price range. If your budget is on the lower side, then consider Canon 1100D and Nikon D3100. After which you can consider Canon 600D, Canon 60D or Nikon D5100 or Nikon D90.

For Sony Alpha, go for its SLT types like Sony A35, A65 and A77 (order of price and performance)

The above will be good dslr camera bodies and if you have the extra cash, consider getting better lenses and other accessory