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PostPosted: Thu Oct 10, 2013 10:07 am 
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Good Day All,

I would finally like to invest in a Fish-eye but i have a few concerns that I would really appreciate help with.

Firstly I have a Canon 60D and would like to purchase the Sigma 4.5mm True Fish-eye.

I understand the advantages of shooting with a Fish-eye but can someone please confirm my concerns below

1. I have done some research with regard to True Fish-eye lenses and the article i read explains that the problem with this type of lens is that lens flares are alot more apparent, they also speak about any light source getting more overexposed then it usually would. This would particularly be an issue when shooting indoor scenes with a view to the outside. Please let me know if anyone has experienced this.

2. My other concern is about quality, the same article explained that you get loss of detail quality when shooting with a Fish-eye due to trying to cram so much into 1 photo.

3. Does the chromatic aberration of a True Fish-eye effect stitching

4. Lastly I have read that the Nodal Point changes on a Fish-eye lens depending on the distance that an object is from the lens, this would be an issue if placed right next to a wall in a room?

5. What is the final file size of a full 360 x 180 stitched panorama when using this type of lens i.e 6 shots

I look forward to your answers and appreciate the help.


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PostPosted: Thu Oct 10, 2013 10:13 am 
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I cannot recommend the Sigma 4.5mm fisheye.

It creates a full circular image on the APS-c sensor of your 60D which means you only need 3 shots (plus optional nadir) but it also means it wastes a lot of pixels and significantly reduces the size (resolution) of the stitched pano

Look instead at the Sigma 8mm f3.5 FE, the Sigma 10mm FE, the Tokina 10-17mm zoom FE, or the Samyang (or branded clone) 8mm f3. 5FE although this a fully manual lens.


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PostPosted: Thu Oct 10, 2013 10:33 am 
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Quote:
Look instead at the Sigma 8mm f3.5 FE, the Sigma 10mm FE, the Tokina 10-17mm zoom FE, or the Samyang (or branded clone) 8mm f3. 5FE although this a fully manual lens.


I would probably look at the Sigma 8mm or 10mm. With regard to the concerns i have with the Fish eye are any of them relevant with either the 8mm or 10mm


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PostPosted: Thu Oct 10, 2013 10:40 am 
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I just phoned my usually camera supplier and they explained that the following

for a 60D the Sigma 10mm will be a Non-Circular Fisheye at R9500

and the 8mm is a circular fisheye at R12100.

Mediavets what do you recommend?


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PostPosted: Thu Oct 10, 2013 11:13 am 
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Wayne Spence wrote:
I just phoned my usually camera supplier and they explained that the following

for a 60D the Sigma 10mm will be a Non-Circular Fisheye at R9500


The Sigma 10mm FE is a fullframe FE - that means you get approx. 180 dgree FOV on the diagonal - and the image covers the entire sensor.

That's' fine - this will produce the highest res. stitched pano.

You will shoot 6-around plus nadir at a min.
Quote:
and the 8mm is a circular fisheye at R12100.


The Sigma 8mm will create full circular image on a fullframe sensor. On the APS-C sensor of your 60D it will created a cropped circular image with some cropped off the long axis sides and a little (on the Canon) cropped from the short axis sides. It creates an image with a 180 degree HFOV on the Nikon DX size cropped sensor but a little less on the Canon APS-C sensor.

You shoot 4-around plus optional nadir and the res. of the stitched pano will be less than than attained using the 10mm FE.

Quote:
Mediavets what do you recommend?


I have a Sigma 8mm f3.5 FE and Nikkor 10.5mm fullframe FE which I use on a Nikon DX (cropped sensor) body. Both bought secondhand years ago at good discounts from new prices.

Both are fine, I find I tend to use the 10.5mm FE more often, but that's because I mostly ushoot interiors with nothing moving in the scene, using a tripod and conventional dual axis pano head (NN4 or NN5).

If you were to shoot outdoor (or indoor) scenes with people and the like then the 4-around with teh Sigma 8mm vs. 6-around with the Sigma 10mm would be an advantage. Poeple also shoot with the Sigma 18mm from a m/needonopod using a ring-style pano head, some have even managed it handheld.

In your situation, given the significant price difference you quote I'd tend towards the 10mm unless there are reasons to want the 8mm.

Could you do a test shoot with each before deciding?


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PostPosted: Thu Oct 10, 2013 12:43 pm 
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No i think i would stick to whichever gives the higher resolution. so thank you for the advice.

As for testing one, i live in a very small town and the camera shop i deal with is 600kkm away from and delivers via courier so no i would have to order one, pay for it and have it delivered.

I am going to take your advise and get the 10mm fisheye.

lastly you didnt answer the question about the flare issue, seeing as you shoot mostly indoors you would be able to help , are the windows more overexposed than with a normal lens?


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PostPosted: Thu Oct 10, 2013 1:14 pm 
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Wayne Spence wrote:
lastly you didnt answer the question about the flare issue, seeing as you shoot mostly indoors you would be able to help , are the windows more overexposed than with a normal lens?


The windows are more overexposed than the rest of the scene when shooting with a fixed manual exposure for all shots but that's to be expected. That's not quite the same thing as flar as I understand it, but I'm no expert.

The answer to that is exposure bracketing (and exposure fusion prior to or during stitching) and the best tool for that (according to those who own one) is the Promote control which enables you to have extended exposure bracketeing over and above the AEB function offered by the camera which is typically inadequate to capture the very large dymanic range for many (most?) pano scenes.

http://www.promotesystems.com/products/ ... ntrol.html


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