Focus Issue: 90mm Elmarit and M8.2

[photolandscape]

I recently bought a new gizmo called a Gigapan Epic 100 for producing large panoramas. Basically, you mount it on your tripod and program it and it proceeds to take the shots. The manufacturer makes two models, and the M8 is about as large and heavy a camera as the Gigapan can handle. After shooting, you process the images with their proprietary software, which does a pretty good job of stitching everything together.

I decided to try it out at Johnston Ridge Viewpoint in Washington, four miles across the valley from the Mt. St. Helens volcano. I programmed the Gigapan to give me 13 horizontal and 5 vertical shots, 65 total.

Using my often spot on 90mm Elmarit (latest model), I set the focus on infinity since the subject was 4 miles away, and did the shots. Aperture was f/8. I did a second series of shots, but set the focus slightly under infinity, just in case the focus was off a bit, and again at f/8. And, I did a panorama with fewer shots, but set at f/11 and again, of the mountain four miles away.

Both times the results were really disappointing. The focus is soft. I would think mounted on a tripod (shutter speed was around 1/60 or higher) at infinity, and f/8, a subject 4 miles away should be quite sharp.

What would you suggest? Do I need to send the lens only, or the lens and body, off to Leica, and if so, to Solms or here to NJ? (Camera is still under warranty). Or send it to DAG? Is there some trick to using this lens on the M8 when it comes to focusing on distant objects? I'm puzzled.

Your thoughts are most welcome.

[Shootist]

Have you check the focus of the lens and camera without this gigapan device since to usd it?
After looking at the device I see a mechanical arm that actuates the shutter release. Count this cause the camera to shake during the exposure.

First I check out the lens and camera mounted on a tripod. If you get clear crisp shots it that device, along with a slow shutter speed, that is causing the blurred, out of focus, images.

[dfarkas]

Originally Posted by Shootist

Have you check the focus of the lens and camera without this gigapan device since to usd it?
After looking at the device I see a mechanical arm that actuates the shutter release. Count this cause the camera to shake during the exposure.

First I check out the lens and camera mounted on a tripod. If you get clear crisp shots it that device, along with a slow shutter speed, that is causing the blurred, out of focus, images.

This is exactly what I am thinking. The first rule in technical troubleshooting is not to try to figure out what the problem is, but rather to first figure out what it is not. Eliminate variables, starting with the Gigapan, as Shootist has described. Also, use either a cable release or a 2sec self timer.

My experience with the Elmarit on the M8.2 is to pull the focus just slightly forward of infinity when shooting at long distances. Not much, just a mm or so on the focus ring. And, I'd stick to f/5.6 or f/8. By f/11 diffraction will rob you of detail. Remember, at these distances, you don't need additional depth-of-field. By shooting in the middle of the aperture range, you will get peak optical quality and a slightly higher shutter speed, which also might solve your Gigapan woes if it is indeed causing unwanted vibrations.

Good luck. Let us know how it turns out.

David

[giordano]

Four miles is enough atmosphere for haze and turbulence to soften and desaturate your shots - so that's another thing to eliminate.

Some suggestions for elimination:
1) On a clear still day put the camera on a solid tripod, turn the focus to infinity, f/5.6, and shoot something about a quarter of a mile away. Turn the focusing ring a millimetre or so and repeat, and once more. Sharp results here tend to eliminate problems with lens or body.

2) At the original site in similar visibility, put the camera on the tripod and shoot as per (1). If the result is similar to your original pano shots, blame the atmosphere. If it's sharp, blame the pano device.

[michali]

I agree with the advice given here. I would also check the whole assembly out at a higher shutter speed, (1/500 and above), as a tele lens over longer distances at 1/60 and even 1/125 will tend to show up camera movement, which may appear to you as lack of focus.

[lars_bergquist]

These suggestions are very good. Eliminate one possible source of error at a time. --Even so, I just got my Elmarit AND my M8 back from Solms, because the focus of the lens was badly off. I bought the lens used, but it is in pristine shape, possibly because its owner could not take sharp pictures with it.

Nothing was done to the camera (I have about one dozen lenses which I want to keep in focus) but the lens is razor sharp now. It took nearly two months of Leica deprivation and cost as much as the price of the used lens, but it was worth it.

The old man from the Age of the 9cm Elmar

[fotografr]

I have the same model lens and mine is spot on with the M8.

[wda]

Originally Posted by giordano

Four miles is enough atmosphere for haze and turbulence to soften and desaturate your shots - so that's another thing to eliminate..

Many years ago I got caught out in a similar way. From my apartment in a foreign city I tried to photograph a notable building about one mile away. After many tests I concluded that it was the invisible heat haze just above intervening roofs which ruled out any hope of sharp pictures. Possibly early morning would beat the atmospheric heat haze.

[lars_bergquist]

'Practical infinity' for any lens is approximately 1000x the focal length, so for a 90mm lens, it is 90 meters. For the belt-and-suspenders folks, double that. But even at that distance, choose a very clear and still morning.

'Strict infinity' does not exist in the physical world. It is a construct in mathematical logic. The moon is at a finite distance. The most distant stars, formed soon after the Big Bang, are some 15 billion lightyears away, but that too is a finite distance.
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I do not imply that all 90mm Elmarit-M lenses are off. Mine was, and had obviously not been tinkered with, so it must have been 'the big one that got away'. Quality control is a human endeavour, humans are fallible, ergo QC is fallible. It was quite fallible in the early days in Solms, but lapses can occur any time.

The old man from the Age of the Screwdriver

[photolandscape]

Thanks for the many good suggestions, and sorry for the delay in responding.

I did some testing and believe that the camera and lens are not at fault. At 1/250 or 1/500 and f/8, distant objects shot through my 90mm Elmarit are sharp. I think I will make some adjustments to the Gigapan--longer times between shots--for example--to let things settle down before firing the shutter. Hopefully that will help.

Back to Mt. St. Helens this weekend. We'll see how it goes.

[epand56]

Photolandscape, just gave a look through your Mount St Helen pictures. They really are breathtaking.

[photolandscape]

Originally Posted by epand56

Photolandscape, just gave a look through your Mount St Helen pictures. They really are breathtaking.

Hello again, thanks for your kind comments about my shots of Mount St. Helens. I was fortunate to climb it in 2000, and equally fortunate to ride with a very confident helicopter pilot who flew us inside the crater, a really amazing experience.

Thanks too for encouraging those of us who made the plunge for the new CV15. It really is excellent, and I am enjoying it immensely.

I did get back to Mt. St. Helems over the weekend, and made my first really successful Gigapan image--actually, 3 images high, and 9 across, which have stitched together and processed in CS3. The final image is 24x88", or 701MB @ 240 dpi. I hope to make a full size print soon. The detail is pretty spectacular. So I think I am on my way. What really made the biggest difference is keeping the aperture at around f/8, and getting the shutter speed set to 1/250 or 1/500 sec. It really increased the sharpness a great deal. So now I am happy with it. Thanks again.