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  #41  
Old 15-02-2012, 08:53 AM
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iceman (Mike)
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Mike, I thought you were looking to purchase *now*, as you said hopefully in 2 months time lots of new gear will be out and you will be able to get the gear you want even cheaper!
Well I do want to purchase now (to get practise in), but I'm happy to wait 2 months if it means prices will be cheaper
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  #42  
Old 15-02-2012, 10:12 AM
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Hi Luigi, you must have an unusually good Samyang, I have had two of the 14mm (one Rokinon, one Samyang) and they were both very, very soft. Way softer than the Nikkor 14-24mm. The lens was fairly well made but had horrible uncorrectable distortion. I wouldn't recommend it unless you could try it for a week first to see if you happened to get a good one.

Mike, I thought you were looking to purchase *now*, as you said hopefully in 2 months time lots of new gear will be out and you will be able to get the gear you want even cheaper!
Maybe you had a bad copy? I've never heard a complain about the Samyang 14mm about sharpnesss.
There's no such a thing as uncorrectable distortion.
The distortion is easy to fix with PtLens. When I notice it I just fix it.
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  #43  
Old 15-02-2012, 10:14 AM
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Maybe you had a bad copy? I've never heard a complain about the Samyang 14mm about sharpnesss.
There's no such a thing as uncorrectable distortion.
The distortion is easy to fix with PtLens. When I notice it I just fix it.
Even with PtLens the distortion is still evident, I have had 2 variants of the lens, others in the camera club have had the same problems.
It is good for the price, but doesn't really compare to the better specimens, though you will pay a *lot* more for them.

The Samyang fisheye is incredibly sharp, but the 14mm is definitely soft, I haven't seen a single sharp one yet. I'd love to see some pictures from yours, I think you got really lucky.
The calibration was also way out on all the models I have seen infinity is usually reached way before the infinity stop. I think with any of these cheapie lenses it is a bit of a lucky dip. I'd buy one if they have a money back guarantee, that way if you get a great one you are set, if you get a dud, you can take it back.
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  #44  
Old 19-02-2012, 05:32 PM
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I did some testing today on lenses and a Canon 40D for your interest Mike.

I tested the famous Nikon 14-24 F2.8 ED, Nikon 24-70mm F2.8 ED, Canon 50mm F1.8, Nikon 50mm F1.8, Canon 28-135mm F3.5, Canon 18-55mm.

I did some panorama shots. The short focal length 14-24 is great by itself but it does not lend itself to panoramas that well. I did one at 24mm and there was definite curving in the panorama.

The Nikon and Canon 50mm F1.8 seemed the same to my very informal and not very precise test. The Canon was better on a 40D of course as autofocus and autoexposure worked.

Interestingly, the panorama included my swimming pool which is quite long and is rectangular and so I had a straight line to contend with.

None of them did the pool without some sort of curve.

If you go too far out (with a zoom) you lose vertical height. If you go too far in you get more curvature. Perhaps that's the way it is.

The 50mm (a very cheap lens comparatively at about $139)
wasn't bad but really needs a fullframe camera as its the equivalent of 85mm and too long.

The 28-135 is what I have used several times and I have gotten excellent results with it. I usually frame it somewhat and select the zoom to suit. I guess I end up around 75mm often.

So my conclusions were:

1. Don't use a tripod unless you have an adapter to get the lenses nodal axis aligned (ie as you pan around you gon't get a swinging effect as the lens is rotating on its optical axis). You are better off simply swinging around holding the camera.

I do a practice swing and make sure I am comfortable and end to end takes in the scene I want.

2. Hold the camera in portrait orientation. It takes a few more images but you get more vertical view in.

3. Around 35-70mm seems best depending on the object and view.

4. Be careful of objects very close to you as they may look odd unless you do the adapter and tripod.

5. Try to make the panorama out of about 4 shots maybe 5. Too many and it becomes this long wide rectangle which is not easy to display.

6. File labelling can be critical. If I were going on a holiday shoot and were going to do many panoramas I would develop a system to identify the start and end of the shoot. I was thinking of a sky shot with my hand in front at the beginning and the end so I know the shots in between all belong to a panorama sequence. It sounds silly but it took me a year to figure out which shots I took of one view were in the same panorama sequence and which were simply happy snaps.

My advice is to become expert at taking 3-5 shot panorama shots and stitch them with panorama factory. It does a great job and its very fast.

A 3-5 shot panorama like that I think is superior to a $2200 exotic lens widefield and you can do it with really modest equipment. So you don't need the absolute best lens to take that super shot.

Out of interest the best 2 of my lenses so far for these panoramas on a 40D are the Canon 28-135mm and the Nikon 24-70 F2.8.

I think I would also aim to shoot the F2.8 at a higher F ratio than F2.8 - maybe F3.5.

Also I use a polarising filter which helps retain sky colour and details (turn it around until you get the best filtering effect).

I think also it may be best to use AV mode on the camera and turn autofocus off. Focus using live view and 10X magnification and manually.
That way the focus, the ISO, the shutter speed (as high as possible as you are hand held) are the same. I think that makes it easier to get a good panorama without bright or dim sections in the sky mainly.

That's what I'd practice over the next 2 months.

Panorama Factory is about US$69.95.
A cheapy Canon 50mm F1.8 would probably be good enough on a 5D or perhaps a bit wider but not much.

These shorter focal length lenses all exhibit varying degrees of curvature that will make a panorama very odd.

Also I wouldn't use those add on lens reducers. The one I got caused nasty aberrations in the outer parts of the images that I did not notice on the LCD but it was obvious on my laptop. But not until I have taken lots of shots.

Greg.
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  #45  
Old 19-02-2012, 05:51 PM
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I know some people knock Ken Rockwell but I like his reviews as they are to the point and help you differentiate between lens quickly.

His recommendation would seem to be this Canon lens:

http://kenrockwell.com/canon/lenses/17-40mm.htm

The problem with a 5D being full frame is all the lense that suit it seem to be expensive. I think if you get a cheap one the camera will probably show up its flaws quite badly.

Greg.
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  #46  
Old 19-02-2012, 06:41 PM
Poita (Peter)
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I totally second the use the camera in portrait mode when doing panorama stitched images.
Also for marking the start and end of panoramas, I take a shot before and after with the lens cap on so I know where they start and stop. My Nikon also allows me to record notes so I am often seen speaking to my camera

I wouldn't be without a wide-angle though, stitched up shots can be great, but with longer exposure times and changing light, such as just before sunrise and around sunset, they can be a challenge.
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  #47  
Old 20-02-2012, 08:06 AM
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Octane (Humayun)
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The 17-40mm lens is a baller.

I don't know why people bag it so much. Maybe because its younger and prettier sibling steals the limelight.

As far as I know, the two things going for the 16-35mm are the extra stop of light, and, its magnificent diffraction spikes at sunrise/sunset. The 17-40mm's diffraction spikes are a dog's breakfast.

I use the 17-40mm at f/16 and it is sharp, sharp, sharp.

You're right, Greg; using cheap lenses on a good sensor is like riding a pogo stick when you own a Ferarri. What's the point?

H
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  #48  
Old 20-02-2012, 08:28 AM
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iceman (Mike)
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Thanks for your thoughts, Greg.

I'll definitely be looking to do lots of panoramas in the Kimberley's and I'm already comfortable with the process for that. I usually use a tripod but curving can definitely be a problem if there's lot of straight lines.

I use AutoPano Pro for creating the panoramas. It's fantastic. Really easy to use and very powerful.

Ken mentioned last week that he may have some Phase 1's available that I can use.. now that would be interesting. I have ZERO experience with medium format cameras. And I think my laptop would die at the thought of processing them
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  #49  
Old 22-02-2012, 03:56 PM
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Quote:
Originally Posted by gregbradley View Post
I did some testing today on lenses and a Canon 40D for your interest Mike.

I tested the famous Nikon 14-24 F2.8 ED, Nikon 24-70mm F2.8 ED, Canon 50mm F1.8, Nikon 50mm F1.8, Canon 28-135mm F3.5, Canon 18-55mm.

I did some panorama shots. The short focal length 14-24 is great by itself but it does not lend itself to panoramas that well. I did one at 24mm and there was definite curving in the panorama.

The Nikon and Canon 50mm F1.8 seemed the same to my very informal and not very precise test. The Canon was better on a 40D of course as autofocus and autoexposure worked.

Interestingly, the panorama included my swimming pool which is quite long and is rectangular and so I had a straight line to contend with.

None of them did the pool without some sort of curve.

If you go too far out (with a zoom) you lose vertical height. If you go too far in you get more curvature. Perhaps that's the way it is.

The 50mm (a very cheap lens comparatively at about $139)
wasn't bad but really needs a fullframe camera as its the equivalent of 85mm and too long.

The 28-135 is what I have used several times and I have gotten excellent results with it. I usually frame it somewhat and select the zoom to suit. I guess I end up around 75mm often.

So my conclusions were:

1. Don't use a tripod unless you have an adapter to get the lenses nodal axis aligned (ie as you pan around you gon't get a swinging effect as the lens is rotating on its optical axis). You are better off simply swinging around holding the camera.

I do a practice swing and make sure I am comfortable and end to end takes in the scene I want.

2. Hold the camera in portrait orientation. It takes a few more images but you get more vertical view in.

3. Around 35-70mm seems best depending on the object and view.

4. Be careful of objects very close to you as they may look odd unless you do the adapter and tripod.

5. Try to make the panorama out of about 4 shots maybe 5. Too many and it becomes this long wide rectangle which is not easy to display.

6. File labelling can be critical. If I were going on a holiday shoot and were going to do many panoramas I would develop a system to identify the start and end of the shoot. I was thinking of a sky shot with my hand in front at the beginning and the end so I know the shots in between all belong to a panorama sequence. It sounds silly but it took me a year to figure out which shots I took of one view were in the same panorama sequence and which were simply happy snaps.

My advice is to become expert at taking 3-5 shot panorama shots and stitch them with panorama factory. It does a great job and its very fast.

A 3-5 shot panorama like that I think is superior to a $2200 exotic lens widefield and you can do it with really modest equipment. So you don't need the absolute best lens to take that super shot.

Out of interest the best 2 of my lenses so far for these panoramas on a 40D are the Canon 28-135mm and the Nikon 24-70 F2.8.

I think I would also aim to shoot the F2.8 at a higher F ratio than F2.8 - maybe F3.5.

Also I use a polarising filter which helps retain sky colour and details (turn it around until you get the best filtering effect).

I think also it may be best to use AV mode on the camera and turn autofocus off. Focus using live view and 10X magnification and manually.
That way the focus, the ISO, the shutter speed (as high as possible as you are hand held) are the same. I think that makes it easier to get a good panorama without bright or dim sections in the sky mainly.

That's what I'd practice over the next 2 months.

Panorama Factory is about US$69.95.
A cheapy Canon 50mm F1.8 would probably be good enough on a 5D or perhaps a bit wider but not much.

These shorter focal length lenses all exhibit varying degrees of curvature that will make a panorama very odd.

Also I wouldn't use those add on lens reducers. The one I got caused nasty aberrations in the outer parts of the images that I did not notice on the LCD but it was obvious on my laptop. But not until I have taken lots of shots.

Greg.
Welcome to the world of panos. Some of your points are right, some are not.

Distortion has nothing to do with the lens or focal length used. Any good panorama software will automatically fix the distortion of the lens. In fact they can be used with a single shot just to fix the distortion.

Curved lines are usually produced by the projection used. A rectilinear projection will keep lines straight but only works for panos of about 90 degrees max. A cilindrical projection works for wider panos but then only the central line is kept straight, that's why keeping the horizon at the center is important in very wide panos.

The best software for panoramas are the descendants from the panorama tools package: PtAseembler, PtGUI and Hugin. The last one is free and the others have trials. You will probably get better results with those programs. Panorama Factory is on the lower end among panorama software.

The polarizer is usually a big no-no in panoramas, you get uneven polarization if you cover a wide area of the sky and that usually looks bad.

Shooting in Av mode is also a big no-no as you get uneven exposure between frames. You should shoot in manual mode with exactly the same exposure, aperture, ISO and WB settings for each frame.

For nightscapes a good quality wide lens is still a need shooting a pano at night is difficult, specially if you need to take several subs for each panel. Once you finish the first panel the stars have moved and stitching and stacking everything becomes a difficult task.
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  #50  
Old 22-02-2012, 04:17 PM
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iceman (Mike)
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Great points Luis!

On a positive note, I'm pretty sure I just got myself a 5D Mark II

Now I need to think about lenses..
The 24-105mm will be standard walkaround, but I want a wide angle for night sky shots and general widefield landscapes. It might not be the same lens..

The 17-40 or 16-35 are my current choices, but one is half the price, but slower
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  #51  
Old 22-02-2012, 04:36 PM
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Go the 17-40mm f/4L USM.

It's stellar for what it is.

Unless, you plan to do lots of night time timelapse stuff, the 16-35mm f/2.8L II USM would be better for the extra stop of light.

H
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  #52  
Old 22-02-2012, 08:11 PM
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For nightscapes a good quality wide lens is still a need shooting a pano at night is difficult, specially if you need to take several subs for each panel. Once you finish the first panel the stars have moved and stitching and stacking everything becomes a difficult task.[/QUOTE]


Thanks very much Luis for your valuable info. I am still learning this subject and appreciate your advice.

Have you used gigapan or autopano?

Greg.
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  #53  
Old 22-02-2012, 08:13 PM
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Quote:
Originally Posted by Octane View Post
Go the 17-40mm f/4L USM.

It's stellar for what it is.

Unless, you plan to do lots of night time timelapse stuff, the 16-35mm f/2.8L II USM would be better for the extra stop of light.

H
Even better get the Nikon 16-35VR as it along with the Nikon 14-24mm F2.8 are widely regarded as the best widefield zooms ever made.

I have a Novoflex adapter I bought and it works really well for using these lenses on a Canonn body. You lose autofocus though. Not that focusing a landscape is hard with live view.

Greg.
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  #54  
Old 22-02-2012, 08:15 PM
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[
Ken mentioned last week that he may have some Phase 1's available that I can use.. now that would be interesting. I have ZERO experience with medium format cameras. And I think my laptop would die at the thought of processing them [/QUOTE]

Wow, now that would be fun!

Greg.
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  #55  
Old 22-02-2012, 10:46 PM
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Originally Posted by iceman View Post
Great points Luis!

On a positive note, I'm pretty sure I just got myself a 5D Mark II

Now I need to think about lenses..
The 24-105mm will be standard walkaround, but I want a wide angle for night sky shots and general widefield landscapes. It might not be the same lens..

The 17-40 or 16-35 are my current choices, but one is half the price, but slower
I didn't like the 16-35 the borders were very bad and at night it had comma up to F5. The 17-40 is also bad for night time photography but it's quite good for landscapes if you use it between F8 and F11.

The 24-105 is a nice lens it's also bad at night but for landscapes it works well from F5.6 to F11 and you need a good RAW processor to fix the distortion. DxO optics does a fantastic job with the 5DII and thw 24-105.

For night sky shots your options are limited. Some lenses that work well that I have testes are:
Canon 28mm F2.8 (and oldie!)
Zeiss 21 F2.8
Nikon 14-24 F2.8 (+ adapter)
Samyang 14mm F2.8
Rokininon 35mm F1.4


Quote:
Originally Posted by gregbradley View Post
For nightscapes a good quality wide lens is still a need shooting a pano at night is difficult, specially if you need to take several subs for each panel. Once you finish the first panel the stars have moved and stitching and stacking everything becomes a difficult task.

Thanks very much Luis for your valuable info. I am still learning this subject and appreciate your advice.

Have you used gigapan or autopano?

Greg.[/QUOTE]

Yes, I have used both. I prefer PtGUI pro, PtAssembler or Hugin even for very large panos.
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  #56  
Old 22-02-2012, 11:16 PM
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DPP has an in-built lens distortion correction facility. Made by Canon.

Luis, I must have an excellent copy of the 17-40mm f/4L USM. I shoot at f/16 and it is sharp at pixel level.

H
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  #57  
Old 22-02-2012, 11:47 PM
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DPP has an in-built lens distortion correction facility. Made by Canon.
Luis, I must have an excellent copy of the 17-40mm f/4L USM. I shoot at f/16 and it is sharp at pixel level.
H
There're good and bad copies of lenses all around. At F16 the 17-40 is as good as at F5.6 maybe slightly better. Unfortunately for nightscapes its bad at F4.
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  #58  
Old 23-02-2012, 07:03 AM
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On the panorama/mosaic softwares this guy tested a lot of them and
decided PTGui was best and Autopano was also very good:

http://www.luminous-landscape.com/fo...hp?topic=15730

I think I'll go with PT Gui Pro as you suggest Luis.

Greg.
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  #59  
Old 23-02-2012, 07:26 AM
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Hi Luis,

Yep, agreed; hence suggesting the faster lens, as per above.

Cheers!

H
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  #60  
Old 23-02-2012, 08:22 AM
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Originally Posted by gregbradley View Post
On the panorama/mosaic softwares this guy tested a lot of them and
decided PTGui was best and Autopano was also very good:

http://www.luminous-landscape.com/fo...hp?topic=15730

I think I'll go with PT Gui Pro as you suggest Luis.

Greg.
PtGUI pro is really very good. I use it from moon mosaics to fisheye panos and it holds its ground.

If you need any help with it send me a PM, email or cablegraph
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