Translation:I will send you photos.
Would also have been better to be "I will send you The photos". "the" is missing.
This sentence could be better with or without "the" depending on the context.
Not much for this sentence, but nowadays 寄 is more associated with the express delivery or post office. Of course we can send (发送, 寄送) the photo by e-mail.
Please also check the dictionary for other meanings of 寄, especially “v. deposit”.
Right. At least in Mainland China, 发照片 and 发邮件 always refer to the electronic method of delivery, whereas 寄照片 and 寄信 imply the physical method. But I think in Taiwan people use 寄 for both.