Mountain Biking Minutes from the Tappanzee!

The traffic was bad on my commute so I drove south on 9A to get to work and passed a promissing bit of woods. I parked here 41° 2'0.97"N 73°50'50.08"W (just my way of keeping it a bit secret!

You would likely do every trail here in about 2 hours but it is truly outstanding practice riding with loads of double track swoopy trails and single track climbing. Great fun for a beginner. Advanced riders just need to go faster! Much like the Atlantic highlands in NJ.

RAW VS JPG Part 1

Have a look at the album to the right of flower images  I shot with D300 and Nikon 105 micro lens. All were shot in the dark of my studio with the sunny WB and no fine tuning of standard plus two saturation of picture control setting. These were shot in near darkness at F16 and ISO 200 at 1/320 with three SB800's shot thru umbrellas as the light source. so they are perfect in terms of not being corruted by differant light sources. The first of each image is the LR conversion from raw to jpg. The second is capture conversion from raw to jpg. (Sorry the caption does make sense I will try to fix it later. )If viewed in nikon Capture the Raw files have identical color to the JPG that you are viewing in this picasa album. RAW viewed in capture NX  look better because of increased shadow detail. In LR however the JPG's look better because of superior green's red's and yellows. Some of you may disagree about the yellows. As you view these images on picasa they are identical to how they would  appear in LR in terms of color and sharpness had you shot raw plus JPG. The LR jpg's have less shadow detail then when viewed in LR as raw files but THE COLOR AND SHARPNESS IS MY ISSUE not shadow detail. Obviously if LR worked correctly the raw would look the same as they do in in capture which is identical in color and sharpness but with better shadow detail and these images would be identical as they would if prcessed in capture (also I cannot post raw files for you to view).

In a perfect world where raw and jpg looked the same and produced the same output in LR and where my computer did not go slower with raw files I would shoot raw all the time. Fact is LR is the best processing software but it does not get color right in raw files. NX nails the colors but sucks for everything but converting JPG and fixing nikon 10.5 images. 

If only LR could handle raw like a camera company software does I would not be whining and trying to decise what format to shoot in. Please note my observations and if you agree let's all start riding adobe to fix this. Please site my observations far and wide. Next up is a studio shoot with skin tones. 

Kenrockwell.com has some great facts about JPG on his website but I have never seen anyone post observations like mine on the web.

My conclusion is not that we should never shoot raw but that we understand the limitations of color and sharpness of raw files if processed in anything other than the camera companies software. 

How to HDR with Canon 5D

As a nikon user switching to canon I found many things I used regularily missing in the canon 5D menus. A big one of concern for shooting HDR is the lack of a mirror delay and 9 stop auto bracketing. So here is how I shoot HDR with my hands tied behind my back. First keep in mind that the optimal exposure must be no slower than 2 seconds for a 7 stop HDR. This is also true for Nikon because the maximum shutter speed is 30 seconds. So set your aperture to f8 for example and shutter to 2 seconds and look for the apropriate ISO to get an image with a perfectly centered histogram. Use the ISO to set your exposure. Now this is the crucial part. If your image has extreme range like a night shot with a bright store window you should start out a little darker. If the image would look interesting with the correct exposure then the centered hisogram is the best starting point. Now once you have this established got three stops over and take your first image. If you went to custom settings and set 1/2 stop exposure steps then go 2 clicks and expose and so on until you hav shot seven. An alternate method is to use canons 3 stop bracketing and do the fist set with the brackets above your optimum and the next set below and including the optimum. If this is too complicated get a nikon!

Flash Duration

Canon does not publish flash duration in their manuals. Nikon does and lists 1/1050 of a second for a full power flash. There are a number of independent testers out there with data from canon flashes but this one I think is signifigant because although the peak is short the trail off at full power makes the effective duration 1/200 of a second. Nikons Published data claims 1/1100 at 1/2 and from there on out the duration halves at each decrease in power.
Why is this important? Because the less work the flash has to do the better it will freeze action. The closer you get your ambient exposure to correct, the less work the flash has to do and thus the shorter the time of illumintion and bettering the ability to freeze action.
Conclusion is that if you set your lens to say 2.8 and the shutter to 1/15 and with the appropriate ISO achieve about 1/2 stop underexposure the flash will fire at 1/4 power or less. This means that if your subject is waving or even clapping the hands will be completly frozen. However if you stop down to F11 and try this there will be motion. Of course decreasing the shutter speed to achieve the same ambient exposure will not help because aperture is what determines the effect of the flash.

tamron 28-75 2.8

This lens is better than you would expect. Decent build quality certainly better than a nikon amateur zoom lens like the 18-70 or 18-55. Sharp in the center even at 2.8. I never used it on full frame. Produces images with excellent dreamy bokeh. I never shot it on full frame. For reasons I don't understand it does occasionally miss focus but good technique reduces this possibility. As far as I am concerned any nikon non AF-S lens has this problem anyway. Perfect focal length for for shooting people. You need this lens if you are shooting a wedding on a budget. There is no substitute for a 2.8 lens. Buy and sell it used it will cost you nothing. Supierior to the 18-200 in brightness and possibly sharpness at these lenghts.
Worst problem is nasty moustache distortion at wide end but this would not be used as a wide lens. Best feature is very decent macro performance and small size. Also I like the zoom lock feature for walking. I rate as excellent taking into account price and size. Nikon prime lenses are brighter and sharper in these focal lenghts but don't have macro or zoom. A nikon 2.8 17-55 or 24-70 are monsters in size and weight in comparison. Perfect walk around lens that does not stick out like pro 2.8 nikon. Oh yes it kind of needs a hood as it does flare quite easily. Don't even think of using stup up rings (67 to 77) as it will flare.
To give you an idea of my taste I think the 18-70 sucks. The 18-200 has unacceptable distortion. The 18-55 is not that sharp as rockwell says. The 17-55 2.8 is Awesome from 24-55. The 105 micro is perfect. The 50 1.8 is super sharp and does not ghost like the 1.4. The 12-24 sucks wider than 18 and the tokina 2.8 11-16 is incredible on a d300. The 70-300VR is the best amateur zoom nikon makes. www.robwouds.com

Wave Hill Class Trip 10/24/08 4:52 PM

Tokina 11-16 2.8 lens for Nikon Review

I have been using this lens since July

 and absolutly love it. I learned about it on kenrockwells site and ordered it before it was available. Trusting Ken's review I sold my nikon 12-24 for $750 before the value started to drop and even before I had the tokina in my hand. Thus I was able to pocket almost $200 and have a superior lens. The only thing I miss is the longer zoom range of the nikon. The 2.8 aperture and the fact that I maunly use it pinned to 11mm make this not so hard to miss. That said if you ever walked around with a 35mm lens on a film camera you know how versatile that focal length is. This is about 20-23mm on a DX nikon and I wish nikon made a super fast 20mm lens with no distortion. When traveling light I carry this tokina and my 35mm F2. 

Everything turned out to be true with this lens. perhaps the most notable thing is that it actually focuses correctly on infinity. The Nikon always left distant objects out of focus because it focused past infinity. 

Next best thing is the minimal distortion. Look at this image at left. I think that there is no distortion worth correcting. The image is sharp with only minor softness and falloff in the corners. Best of all this is at 2.8 1000 iso  and 1/8. I shot three images in C mode and picked this one as it had no blur. Pushing the shutter button shakes the camera so let it fly and pick the best image. 

Anyone that doubhts the value of fast lenses should do this test. Shoot say a 18-70 at 50mm at 5.6 in dim light that calls for 1/30 of second. Now take the same shot with a 50mm 1.8 lens using f5.6 as well. The differance is staggering. Try the same in bright light and it will not be as noticable. Want to see more from this lens try this link.