Girlfriend thinks I Cheating, HELP

... I wouldn't worry about the difference in light gathering between f5.6 and f6.3 tbh :smashin:

It's not a lot of light but can give an edge.

More important, and I forgot to mention before it also effects which autofocus points work. Need to check the manual, but I recall 5.6 being the minimum for AF points to work on a lot of canons. For 6.3 might be limited to center point only or possibly liveview still works I can't recall exactly.
 
It's not a lot of light but can give an edge.

More important, and I forgot to mention before it also effects which autofocus points work. Need to check the manual, but I recall 5.6 being the minimum for AF points to work on a lot of canons. For 6.3 might be limited to center point only or possibly liveview still works I can't recall exactly.
It's weird as it didn't make a difference on the older Nikon 51 point AF but it does on the newer 153 point AF system, ie you get the reduced AF points at the long end using f6.3 lenses.
 
It's weird as it didn't make a difference on the older Nikon 51 point AF but it does on the newer 153 point AF system, ie you get the reduced AF points at the long end using f6.3 lenses.

I must be miss remembering, perhaps 5.6 is the limit for cross-type AF? Sorry for the confusion.
 
I must be miss remembering, perhaps 5.6 is the limit for cross-type AF? Sorry for the confusion.
Depends on the camera, most can now shoot with a max effective aperture of f8 but you are restricted on the focus points, some being centre AF point only. Most will allow use of all AF points using lenses with a max aperture of f5.6, but f6.3 is somewhere in between so on some cameras (like the D750) I could use all AF points using an f6.3 lens at the long end, yet on the D500 and D850 only a limited number of AF points worked using an f6.3 lens at the long end.

The manual will tell you what AF points are usable at what max aperture, but they're only listed in full stops, therefore if you have one that's an 'in between' stop aperture it's a case of try it and see.
 
Here's an outside the box suggestion. Buy her a new Canon 90D 32Mpixel body. It will cost the same or less than the cheapest of your canon lens options. It has almost 1.8 times the number of pixels of her current 18Mpixel camera, so for the same image resolution, she can use digital zoom in combination with telephoto zoom to get close up images from a 300mm lens comaparabe to having a 540mm lens. (this is actually mooted in the sale spec of this camera). Her current 250mm lens will operate as a 450mm lens, for images at the same resolution as her existing camera. A 300mmm canon lens can be bought for about €120, or Aus$190. She ends up with a much lighter setup than either the 400 or 600 lens, has access to twice the resolution for non digital zoom work, and has a spare 600D camera body, to sell or trade for another lens. If it was my own kit, that's how I would be thinking.
 
Here's an outside the box suggestion. Buy her a new Canon 90D 32Mpixel body. It will cost the same or less than the cheapest of your canon lens options. It has almost 1.8 times the number of pixels of her current 18Mpixel camera, so for the same image resolution, she can use digital zoom in combination with telephoto zoom to get close up images from a 300mm lens comaparabe to having a 540mm lens. (this is actually mooted in the sale spec of this camera). Her current 250mm lens will operate as a 450mm lens, for images at the same resolution as her existing camera. A 300mmm canon lens can be bought for about €120, or Aus$190. She ends up with a much lighter setup than either the 400 or 600 lens, has access to twice the resolution for non digital zoom work, and has a spare 600D camera body, to sell or trade for another lens. If it was my own kit, that's how I would be thinking.
Good idea in theory but the more you crop a lens the more you degrade image quality, plus a 1.6 crop of a 32mp image ‘only’ gives 12mp :smashin:
 
Here's an outside the box suggestion. Buy her a new Canon 90D 32Mpixel body. It will cost the same or less than the cheapest of your canon lens options. It has almost 1.8 times the number of pixels of her current 18Mpixel camera, so for the same image resolution, she can use digital zoom in combination with telephoto zoom to get close up images from a 300mm lens comaparabe to having a 540mm lens. (this is actually mooted in the sale spec of this camera). Her current 250mm lens will operate as a 450mm lens, for images at the same resolution as her existing camera. A 300mmm canon lens can be bought for about €120, or Aus$190. She ends up with a much lighter setup than either the 400 or 600 lens, has access to twice the resolution for non digital zoom work, and has a spare 600D camera body, to sell or trade for another lens. If it was my own kit, that's how I would be thinking.

This doesn't work in practice because the pixels between the two setups are not equivalent so when you aggressively crop the 32MP image you may still end up with a reasonable number of pixels but you're using a much smaller portion of the sensor which will degrade the image quality.
 
This doesn't work in practice because the pixels between the two setups are not equivalent so when you aggressively crop the 32MP image you may still end up with a reasonable number of pixels but you're using a much smaller portion of the sensor which will degrade the image quality.
Yep, pretty much what I said above :smashin:

The ‘crop’ in question would be a 12mp image that has been ‘magnified’ and therefore enhancing the flaws resulting in a degraded image.
 
Apologies, I'm using the pixels as the basis. The 90D 6960 X 4640 image is 1.8 times the 600D image of 5184 X 3456, so cropping the 90D to this size will give the same size image. The increase in digital zoom is of course two dimensional, so cropping from D90 to to D600 size will not be equivalent to to a zoom increase of 1.8, but rather the square root of 1.8, which is the increase in size of the D90 in both dimensions, 1.342 this would still push a 300mm lens to a 400mm, which is a substantial increase in image zoom for no image resolution loss.
 
Apologies, I'm using the pixels as the basis. The 90D 6960 X 4640 image is 1.8 times the 600D image of 5184 X 3456, so cropping the 90D to this size will give the same size image. The increase in digital zoom is of course two dimensional, so cropping from D90 to to D600 size will not be equivalent to to a zoom increase of 1.8, but rather the square root of 1.8, which is the increase in size of the D90 in both dimensions, 1.342 this would still push a 300mm lens to a 400mm, which is a substantial increase in image zoom for no image resolution loss.
Yeah I understood that but I think you confused me with your different focal lengths using 250 and 300mm as the start point.

To keep things simple:-

The 250mm lens on the OP's camera gives a 400mm effective focal length at 18mp
A 250mm lens on the 90D uncrossed gives a 400mm effective focal length but with 32mp

If you crop to an 18mp image on the 90D you'd need to crop by 1.342 as you say. 400mm x 1.342 = 536mm focal length. However, you have magnified the image and degraded the quality.

A 400mm lens on the OP's body would give a 640mm effective focal length with no reduction in IQ :smashin:
 
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I get what you're saying,
"If you crop to an 18mp image on the 90D you'd need to crop by 1.342 as you say. 400mm x 1.342 = 536mm focal length. However, you have magnified the image and degraded the quality. "
but what I'm saying is the increased resolution of the sensor chip means that you can match the resolution of the 600D by cropping to the central pixels of the sensor, the 5184 by 3456 in the middle of the 6960 X 4640 of the 90D. Your final image is the same as the 600D best resolution, but is effectively zoomed in on centre of the full frame image presented by the lens, 250mm, 300mm or otherwise. I don't see how a 5184 by 3456 image cropped from the center of the higher resolution sensor would be of any less quality than the entire full frame image from the sensor of the lower resolution camera. Sure it would not be as good as it's own 90D full resolution, but the OP only has a 600D, so the best they can get is it's lower resolution anyway, and if they are happy with that, then the cropped higher res sensor image will be the same, not degraded.
If anything, image distortions at the periphery of the objective image on the sensor would be less, as you are only using the central 58% of the lens collected image. Don't take my word for it, this from Canon's own site;
"The EOS 90D is built around an 32.5MP APS-C sensor that gives lenses 1.6x the telephoto reach they would have on a full-frame camera. Great for those times when you need to be right in amongst the action."
They are basically promoting the digital zoom capabilities of the camera.
See Canon EOS 90D Camera - Canon Ireland
Anyway, the OP should discuss this with a Canon retailer, try a few trial shots with both bodies, that's if anyone buys from a real shop these days.
 
Yep, pretty much what I said above :smashin:

The ‘crop’ in question would be a 12mp image that has been ‘magnified’ and therefore enhancing the flaws resulting in a degraded image.

Just wanted to back you up :)
 
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Just wanted to back you up :)
No, what I meant was that the crop would be an 18Mpixel image, taken from the full frame at the ratio of 1/1.8. This results in a same sized image as the 600D, but the equivalent zoom and lens multiplier is not 1.8, but sq root of that, 1.342. Canon themselves are claiming 1.6
 
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No, what U meant was that the crop would be an 18Mpixel image, taken from the full frame at the ratio of 1/1.8. This results in a same sized image as the 600D, but the equivalent zoom and lens multiplier is not 1.8, but sq root of that, 1.342. Canon themselves are claiming 1.6

I've added bold to the post above since it wasn't clear to you.

The number of pixels does not solely determine the image quality otherwise everyone would be buying the new 108MP camera sensor as even with a heavy crop would still offer more pixels than most FF and APS-C cameras but even at full resolution its IQ would be far below a larger sensor.

Aside from the fact I disagree with the marketing for crop cameras as having a telephoto advantage, an APS-C sensor offers less image quality than an FF sensor and that's not what you're proposing either. You're suggesting starting with a smaller sensor and taking a much larger crop so the resulting image area which would take it down to around a 1in sensor. Given the OP's partner has a decent body already but a limited choice of lenses and they want longer range, it doesn't make any sense to buy a higher MP body and heavily cropping it since they're going to get poorer results than a longer lens.
 
No, what I meant was that the crop would be an 18Mpixel image, taken from the full frame at the ratio of 1/1.8. This results in a same sized image as the 600D, but the equivalent zoom and lens multiplier is not 1.8, but sq root of that, 1.342. Canon themselves are claiming 1.6
I think you're mis-reading what Canon are quoting. Canon APS-C cameras have a crop factor of 1.6, it's nothing to do with how many pixels but down to the size of the sensor. They say themselves that it's a 1.6x crop advantage over full frame, NOT other APS-C cameras. The 600D, 90D etc etc all have the same crop factor, ie 1.6. Nikon, Fuji and Sony APS-C cameras have a crop factor of 1.5, and M4/3 have a crop factor of 2. All of these are regardless of how many pixels they have :smashin:

If you want to crop in post processing, or using digital zoom there is no set crop factor as it purely depends how much you crop in post/digitally zoom. You could have a crop factor of 5 if you wanted, but your image would look shocking ;)
 
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Monopods are useful as they take the weight of the camera and lens,... when stationary. However, walking around you obviously have to carry the gear, which if you have a monopod means carrying this too. Some also find shooting with monopods awkward as they can hinder your movement when shooting.

Just for your info 150-600mm lenses weight 1.9-2kg, whereas the Sigma and Tamron 100-400mm lenses weigh around 1kg. Now we all want long reach, but I’m a big guy (6’4”) and I found carrying 3kg of gear (150-600mm plus camera) around zoos etc tiresome. Going out into the countryside was even more of a chore.

I’ve actually now swapped systems for wildlife and have the Olympus EM1-II and 100-400mm which gives me effective focal length of 200-800mm and a package weighing 1.4kg in total :smashin:

I use a spring loaded telescopic photographer's walking pole with a quick mount system on the top. Two of them are very useful on wildlife treks, and if you can find one that telescopes out to 1.5m then you can even use one with a camo tarp to make an emergency shelter or a hide.
 
If she's shooting wildlife, she probably won't have the luxury of a monopod or better. I've gotten away with crazy stuff using the Canon EF 100-400mm f4.5-5.6L IS II USM because of the image stabilization that helps compensate when you're shooting from a moving vehicle or in low light. Its super-sharp which is even more important with wildlife photography where the cropping when processing is part of the process. If £1,330 isn't too rich for your blood, I'd recommend it.
 

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I'd go for the 100-400mm. It is smaller and a stop faster. It is seriously difficult to keep a 600mm lens steady without a good tripod, soo the slightly faster 400mm will be a better compromise.
 
I dont know a lot about system cameras, Im more of a 3d video guy, but i Was curious of the size of a 600mm and if it would be doable to have a good stabilizing solution without a tripod.
So after some googling i landed on tripods and what i THINK is a 600 vs 400 mm objective diameter
And for shooting on tripod he shows 2 pretty good solutions without going full electrical gimball. (Unless the big one is electrical, but it doesnt look like it)
If the big one is 600mm and the other one 400mm i can understand the comments on weight....damn thats the kind of lens reporters shoot snoop photos of celiebrities with :)

Maybe this is of no help and please correct me if this is not 600 vs 400mm lenses.
Regardless of size the tripod solution he used for ie shooting birds and being able to rotate the cameras seems nice and in two variants.



Also this comparison might help to choose
(He seems to like/recomend the Tamron 150-600mm the small-ish one (400mm) as a general lens..I mean considering he seems to be a pro i think all three are good),
if choice is an option :) Maybe you should try to figure out a bit more by talking with GF what she will use another lens for, if she will just have it tripod mounted in-house or if SHE SECTETLY plans a Africa Savannah trip for you too in xmas present (and thus need a portable lens probably) ;-)
 
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Isnt it possible to"rent a lens"?
Then you could rent her three lenses and supply a gift card to buy one of them for Xmas :)
Then she would get exactly what she likes.

I personally would not like someone else to decide for me which 3d video equipment to buy unless it's someone with good knowledge that knows my needs. But still i understand you want to show you put your time into three subject, but that doesn't mean you have to choose. She will probably be just as glad to hear you taking about aperture, focal length and so on but explaining in the end it felt impossible to choose and then a gift card or rent + gift card solution.

But not sure if your gf is as picky as me, generally girls are not as focused on the tech as they are on the love and thought behind it from the gift bringer:)

So I would read up a bit so you can discuss photography on a low level at least :) and then let her choose final product (to be sure it gets right) maybe after a few rent lenses :)
 
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Isnt it possible to"rent a lens"?
Then you could rent her three lenses and supply a gift card to buy one of them for Xmas :)
Then she would get exactly what she likes.

I personally would not like someone else to decide for me which 3d video equipment to buy unless it's someone with good knowledge that knows my needs. But still i understand you want to show you put your time into three subject, but that doesn't mean you have to choose. She will probably be just as glad to hear you taking about aperture, focal length and so on but explaining in the end it felt impossible to choose and then a gift card or rent + gift card solution.

But not sure if your gf is as picky as me, generally girls are not as focused on the tech as they are on the love and thought behind it from the gift bringer:)

So I would read up a bit so you can discuss photography on a low level at least :) and then let her choose final product (to be sure it gets right) maybe after a few rent lenses :)
Renting works out quite pricey.
 

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