-
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
300mm f2.8....A decent walkabout lens? (1 Viewer)
- Thread starter Gaz Shilton
- Start date
Chris B.
Well-known member
I've been away from this site for quite some time but thought I'd weigh in since I use a 300f2.8L IS with a 2x converter all the time...Although I do own and use a 100-400, the performance of the 300+converters is nothing short of phenomenal. Most of the osprey and eagle shots on my website were made with this combination. But, be forewarned, it's not a lightweight combination... I use mine on either a Wimberley equipped tripod or a monopod.... or on a beanbag from the car. If you need something to lug around in your travels, seriously look at a 400mm f4 DO.
Chris
Chris
Gaz Shilton
Well-known member
I have looked at the 400 f/4 DO, but for the price of it you can get the 300/2.8 with converters/ tripod/wimberley sidekick/camera all roughly for the same price as that lens on its own. I know which direction my wife wants me to go with this. The 300/2.8 is the way forward for me I think still. Saw a chap at the weekend with the Nikon equivalent and after chatting to him I still think the Canon version is the better option.
Gaz Shilton
Well-known member
With a 1.4x and 2x on a 300/2.8 you get 420mm at f4 and 600mm at f5.6 repectively. Do these not increase with a camera that has a 1.6x cropfactor (40D)? Does the difference show noticeably?
Roy C
Occasional bird snapper
It is field of view and not focal length that changes with a crop camera so with a 300/2.8 + 2x tc on a 1.6 cropper you get a FOV akin to a 960mm lens.
IMO there are advantages to using a 1.6 cropper as it concentrates all the pixels to the part of the image that generally contains the bird. I did see a couple of shots the other day of the same subject with the same lens and distance, one with a 1.6 cropper and one with a 1.3 cropper (1D mkIII) and was surprised how much bigger the bird looked from the 1.6 crop shot. The difference between a 1.6 cropper and a full frame would be greater still. Of course subject size is only one part of it, the 1.3 and full frames will probably give better IQ and high ISO noise performance.
Last edited:
Gaz Shilton
Well-known member
Thank you for clearing that up for me Roy C.
paul goode
Well-known member
Isn't field of view measured in degrees not mm?
Gaz Shilton
Well-known member
Excuse my ignorance, but, I have always thought (probably wrongly) that a 1.6x crop factor on a camera gave your lens more 'reach' than a 1.3x or a full frame camera.
I must have mis-interpreted what I have read on other websites.
I must have mis-interpreted what I have read on other websites.
Last edited:
tdodd
Just call me Tim
When you stick a 400mm lens on the front of a camera the size of the subject projected onto the sensor is going to be the same, whether the camera is full frame, 1.3X crop or 1.6X crop.
e.g. Take a look at the image here - http://digital-photography-school.com/wp-content/uploads/2008/08/full-frame-crop-factor.jpg. It's not my image so I won't attach it. Please follow the link. Now, imagine that in the centre of that photo you have your subject - a bird, rabbit, person, whatever. The size of the sensor will make not a scrap of difference to the size of the subject as recorded at the sensor. If the subject occupied 10mm of height on a 40D sensor it would occupy 10mm of height on a 1D3 sensor and 10mm of height on the sensor of a 5D2 as well. There is no extra magnification achieved, or extra reach, through having a smaller sensor. You simply end up recording less of the scene as a whole, which if you are short on focal length is absolutely fine. You save money on the body and end up with smaller files that aren't full of pointless pixels that you will need to crop out later.
So, as far as sensor size is concerned, rather than thinking of the cropped bodies as offering more "reach", think of it as the larger sensor bodies including more of the scene. The actual subject recorded on the sensor is the same physical size (in mm, not pixels) regardless.
Where the difference in "reach" does lie is in pixel density. Quite simply, if the image of your subject projected onto the sensor is the same physical size, regardless of sensor size, then the camera with the highest pixel density will place more pixels onto your subject. If you have more pixels on your subect then you should have more fine detail recorded. Of course, there is no free lunch, and generally it is true that smaller pixels, which cannot gather as much light as larger ones, will each be a litle noisier. But add the pixels together to form the image as a whole (instead of pixel peeping) and you should see more detail in your image.
If you really want to see better IQ then you do need a larger sensor, and longer glass to fill it, so that you project a larger image onto the larger sensor and end up with far more light captured and a superior image all round. Real "reach" comes from using longer glass. For those of us on a budget we have to make up for lack of real reach by having cameras with higher pixel densities.
Even with that said, you may find that due to factors such as blur, shake, noise, misfocus, soft lens etc. that you cannot gain much advantage, if any, from higher pixel densities, because unless your capture is perfect, all they will do is more accurately record the flaws in your image capture.
To put this another way, I find that for BIF I will typically get just as much "reach" from my 1D3 as from my 50D. This is because through combinations of blur/shake/misfocus (even if only by an inch or two), noise and so on, all that the 50D really does is to reveal the softness of the capture unless my photography is perfect, which it mostly isn't. The larger pixels of the 1D3 tend to obscure slight flaws in sharpness, as well as being individually less noisey, and that gives me files that are easier to work with.
But, for perched birds, where I do not need super high shutter speeds, or high ISOs, and when I can nail focus perfectly, and when I can fully control camera shake, the 50D can pick out details that the 1D3 will miss. Thus, in simple terms, I find the 1D3 to be the better camera for things that move fast, or anything in poor light, and the 50D is better for things that barely move, and are bathed in good light. Horses for courses - right tool for the job. If you're on a budget and want something that falls between those two extremes then the 40D seems the ideal compromise. If only it had AF microadjustment.
Last edited:
Roy C
Occasional bird snapper
Not according to Wikipedia - quote "Although related, FOV is not exactly the same as angle of view; FOV is measured in linear, spatial dimensions (feet, inches, metres, etc) whereas AOV (more properly called the angular field of view) is measured in degrees of arc. FOV increases with distance, whereas AOV does not. FOV changes as the camera rotates, AOV does not. Thus, while AOV is used for lens design specification, FOV is more useful to the photographer "in the field".
p.s. I have edited my original post just for you Paul :t:
Last edited:
paul goode
Well-known member
The knowledge base has moved on since I where a lad. It was just fov in degrees when I was wielding a Zenit EM :-O
tdodd
Just call me Tim
My understanding of FOV comes from binocular optics, where you might see the FOV described as 345 feet at 1000 yards for an 8X pair of bins - examples here - http://www.sportoptics.com/Swarovski-Pocket-Binoculars.aspx.
AOV is pretty obviously an angular description. While the two are directly related, they are two very different ways of describing what is effectively the same thing. If I've remembered my trig right, from 30+ years ago,
FOV = 2 x tan(AOV/2) x subject distance
so it is possible to convert directly back and forth between the two methods of expressing the view, should you be so inclined.
To my mind, it is far easier to visualise FOV than AOV. e.g. if the FOV is 345' at 1000 yds then it will be 34.5' at 100 yds and 3.45' at 10yds. Bins of 10X mag have a FOV of 285' per 1000yds, which in very roughly rounded terms is close to 1yd of width for every 10yds of distance, or 1m of width for every 10m of distance. That information easily allows me to judge whether those optics will be suitable for viewing birds, or anything else, of any given size at any given distance. If, on the other hand, you told me my optics had an AOV of 1 degree, 2 degrees, and so on, then I'd have no clue how useful those optics would be to me in practice, without looking up FOV equivalency.
Of course, it follows that if you could memorise the FOV for a given focal length - say 100mm - when coupled to a specific size of sensor, then you could easily derive any other FOV for other focal lengths by simple multiplication/division. e.g. a 400mm lens would have an FOV 1/4 as wide, a 600mm lens would be 1/6th as wide, a 50mm lens would be 2X as wide etc..
AOV is pretty obviously an angular description. While the two are directly related, they are two very different ways of describing what is effectively the same thing. If I've remembered my trig right, from 30+ years ago,
FOV = 2 x tan(AOV/2) x subject distance
so it is possible to convert directly back and forth between the two methods of expressing the view, should you be so inclined.
To my mind, it is far easier to visualise FOV than AOV. e.g. if the FOV is 345' at 1000 yds then it will be 34.5' at 100 yds and 3.45' at 10yds. Bins of 10X mag have a FOV of 285' per 1000yds, which in very roughly rounded terms is close to 1yd of width for every 10yds of distance, or 1m of width for every 10m of distance. That information easily allows me to judge whether those optics will be suitable for viewing birds, or anything else, of any given size at any given distance. If, on the other hand, you told me my optics had an AOV of 1 degree, 2 degrees, and so on, then I'd have no clue how useful those optics would be to me in practice, without looking up FOV equivalency.
Of course, it follows that if you could memorise the FOV for a given focal length - say 100mm - when coupled to a specific size of sensor, then you could easily derive any other FOV for other focal lengths by simple multiplication/division. e.g. a 400mm lens would have an FOV 1/4 as wide, a 600mm lens would be 1/6th as wide, a 50mm lens would be 2X as wide etc..
Last edited:
Gaz Shilton
Well-known member
Tim,
Thank you for putting into words I can understand.
And the link makes the understanding even clearer. As they say, a picture paints a thousand words.
Fantastic
Thank you for putting into words I can understand.
And the link makes the understanding even clearer. As they say, a picture paints a thousand words.
Fantastic
Now you are thinking....sure, you can do the 500 or 600 thing and have to hire out laborers to haul all of your stuff or you can get the 300 (I have the F4L) and with a TC...or not, you can get about all.
If you work for National Geographic and are doing a photo shoot, go for the 500 or 600mm...otherwise...go for the lighter, easier to handle, no mono or tripod needed....300mm
Roy C
Occasional bird snapper
Sure the 300/2.8 is lighter than the 500/4 but bringing the 300/4 into the equation is irrelevant - do you realise that the 300/2.8 is more than double the weight of your 300/4?
jalethbridge
I like sea-watching
I have the portability issue, although I already have the lense, and it is awesome. I prefer not to use it with TCs though. It is almost certainly my technique, as I hate tripods, but with the 1.6x, I find it impossible to avoid camera shake and adding tcs seems to be the tipping point. Photos improve immeasurably if you use a tripod though, even with just the bare lense. 3.25kg is actually a lot to hold steady.
One thing I would draw attention to is that the DOF at f2.8 can be measured in fractions of a mm, which in practical terms for bird photograpy where you need to get in close to get something large enough in the frame, means you need you need to stop down to get acceptable results. I find I use my lense at f6.3 or indeed smaller most of the time. This flys in the face of lugging around 2.5kg for the amount of light it lets in. This problem does not exist with the f4 lense, or at least not for me. I am able to use it wide-open most of the time.
The portability issue is one which I struggle with. I am off to Scilly this autumn, and I am birder first, photographer second. I want to have a scope. That means a tripod. Bins go without saying. Then I need food and coffee. And I also want to take photos. I carry the camera and 300 2.8 (hood reversed) in a small lowepro flipside thing, which also takes a flask of coffee in the side and can carry a wide angle, both TCs, and if necessary the small 70-200. This is a lump though. So I would have that, bins round my neck, and a tripod + scope + ball-head (not light) over my shoulder. Personally I don't think I can do a day in the field, walking perhaps 20 miles, with all this. Then again, substituting the f4 for the f2.8 saves less than 1.5kg. This will be noticeable, but hardly substantial over the course of a day. Anyone have any thoughts? Ditch the scope and tripod perhaps? Maybe you just can't bird and take decent photos, and you have to choose one over the other.
I tend to carry the f4 locally, as I have been mugged on my patch, thankfully without camera that time, but I would hate to lose the 2.8. You stand out less, you can bung it in a small, non-obviously photographic bag.
Jonathan
PS, majority of bird photos on the blog were taken with the 2.8. Have a look at some of the ones in the post titled "A trip". Used a tripod for the Black Guillie, I really think it makes a difference.
One thing I would draw attention to is that the DOF at f2.8 can be measured in fractions of a mm, which in practical terms for bird photograpy where you need to get in close to get something large enough in the frame, means you need you need to stop down to get acceptable results. I find I use my lense at f6.3 or indeed smaller most of the time. This flys in the face of lugging around 2.5kg for the amount of light it lets in. This problem does not exist with the f4 lense, or at least not for me. I am able to use it wide-open most of the time.
The portability issue is one which I struggle with. I am off to Scilly this autumn, and I am birder first, photographer second. I want to have a scope. That means a tripod. Bins go without saying. Then I need food and coffee. And I also want to take photos. I carry the camera and 300 2.8 (hood reversed) in a small lowepro flipside thing, which also takes a flask of coffee in the side and can carry a wide angle, both TCs, and if necessary the small 70-200. This is a lump though. So I would have that, bins round my neck, and a tripod + scope + ball-head (not light) over my shoulder. Personally I don't think I can do a day in the field, walking perhaps 20 miles, with all this. Then again, substituting the f4 for the f2.8 saves less than 1.5kg. This will be noticeable, but hardly substantial over the course of a day. Anyone have any thoughts? Ditch the scope and tripod perhaps? Maybe you just can't bird and take decent photos, and you have to choose one over the other.
I tend to carry the f4 locally, as I have been mugged on my patch, thankfully without camera that time, but I would hate to lose the 2.8. You stand out less, you can bung it in a small, non-obviously photographic bag.
Jonathan
PS, majority of bird photos on the blog were taken with the 2.8. Have a look at some of the ones in the post titled "A trip". Used a tripod for the Black Guillie, I really think it makes a difference.
Last edited:
